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Medical Dictionary: p

Word	Definition
p	after
p wave	Marks atrial depolarization. In a normal EKG, it precedes the QRS complex.
P-A	posteroanterior
p.c.	after meals
p.r.n.	as needed
PA	Physician Assistant
PAC	premature atrial contraction
pacemaker	A device designed to use electric impulses to simulate heart contractions.
pachy-	thick
Paco2	partial pressure of carbon dioxide in alveolar gas
PAD	peripheral arterial disease
PAF	platelet activating factor
pain	An unpleasant or distressing localized sensation induced by noxious stimuli which are detected by nerve endings of nociceptive neurons.
palat/o	palate
palate	The structure that forms the roof of the mouth. It consists of the anterior hard palate and the posterior soft palate.
pale/o	early, primitive, old
palliative medicine	A branch of medicine concerned with preventing and relieving the suffering of patients in any stage of disease and improving the quality of the patient's life.
pallor	A clinical manifestation consisting of an unnatural paleness of the skin.
palpation	Use of fingers with light pressure as part of a physical exam.
palpebr/o	eyelid
PALS	pediatric advanced life support
pan-	all
pancreas	An irregularly shaped gland, located behind the stomach, that secretes pancreatic juice into the duodenum and insulin, glucagon, and somatostatin into the bloodstream.
pancreat/o	pancreas
pancreatectomy	Removal of the pancreas.
pancreatitis	Inflammation in the pancreas.
pandemic	A widespread epidemic of infectious disease.
panic	A state of extreme acute, intense anxiety and unreasoning fear.
panic attack	Fear response that is out of proportion for the situation.
panniculitis	General term for inflammation of adipose tissue, usually of the skin, characterized by reddened subcutaneous nodules.
pant/o	whole, all
panuveitis	Inflammation of both the anterior and posterior segments of the uvea tract.
Pap	Pap test Papanicolaou smear
papill/o	nipple, optic disc
papilla	A small, nipple-like projection.
papilledema	Swelling of the optic disk due to increased intracranial pressure.
papilloma	A benign epithelial tumor derived from epithelium and projecting from the surrounding surface
papul/o	papule, pimple
papule	A solid raised lesion that has distinct borders and is less than 1 cm in diameter.
-para	to bear offspring
para-	similar, beside
paradox	A statement, finding or condition, that, despite apparently sound reasoning from true premises, leads to a self-contradictory or a logically unacceptable conclusion.
paraffin	A mixture of solid hydrocarbons obtained from petroleum.
paraganglioma	A neoplasm derived of the tissue composing the paraganglia.
paralysis	Loss of muscle function.
paramedical	Pertaining to certain adjunctive healthcare professions, particularly trained emergency responders.
parametritis	Inflammation of the parametrium, the connective tissue of the pelvic floor.
parametrium	The lateral extension of the uterine connective tissue into the broad ligament.
paranasal sinuses	Air-filled cavities located around the nasal cavity. There are four pairs: frontal, sphenoid, maxillary and ethmoid.
paranoia	Overly suspicious behavior.
paranoid behavior	Behavior exhibited by individuals who are overly suspicious, but without the symptoms characteristic of paranoid personality disorder or schizophrenia.
paranoid disorders	Chronic mental disorders in which there has been an insidious development of a permanent and unshakeable delusional system, but with clear and orderly thinking. Emotional responses and behavior are consistent with the delusional state.
paraparesis	Weakness or partial paralysis of the lower extremities.
paraphasia	A condition in which the patient uses wrong words, creating unintelligible sentences.
paraphimosis	A condition in which the foreskin, once retracted, cannot return to its original position. If this condition persists, it can lead to painful constriction of glans penis, swelling, and impaired blood flow to the penis.
paraplegia	Paralysis affecting the legs.
parasite	Invertebrate organisms that live on or in another organism.
parasomnia	Any of a group of sleep disorders characterized by unwanted behaviors or perceptions that occur during sleep or partial arousal from sleep, including sleepwalking, night terrors, and frequent nightmares.
paratenon	The fatty or synovial tissue between a tendon and its sheath.
parathyroid glands	Two pairs of small oval-shaped glands located in the front and the base of the Neck and adjacent to the two lobes of thyroid gland. they secrete parathyroid hormone that regulates the balance of calcium; phosphorus; and magnesium in the body.
parathyroidectomy	Surgical removal of one or more parathyroid glands.
paresis	A general term referring to slight or incomplete paralysis.
-paresis	weakness, slight paralysis
paresthesia	A sensation of tingling or numbness, skin crawling, or itching without apparent cause.
parietal bone	One of a pair of irregularly shaped quadrilateral bones situated between the frontal bone and occipital bone, which together form the sides of the cranium.
parietal lobe	Upper central part of the cerebral hemisphere. It is located posterior to central sulcus, anterior to the occipital lobe, and superior to the temporal lobes.
parity	The number of viable offspring a female has borne.
Parkinson disease	A progressive disease of the nervous system that affects movement.
paronychia	An infection of the skin around a fingernail or toenail.
parotid gland	Either of the pair of salivary glands that lie on the sides of the face immediately below and in front of the ear.
parotitis	Inflammation of the parotid gland.
paroxysm	A spasm or convulsion.
paroxysmal supraventricular tachycardia	A very rapid heartbeat that occurs sporadically. Usually lasts from a few seconds to several hours.
-partum	childbirth
parturition	The act of giving birth to one or more offspring.
pasteurization	Heating of certain beverages, such as milk, to a specific temperature for a fixed time interval in order to kill microorganisms.
PAT	paroxysmal atrial tachycardia
patella	The flat, triangular bone about 5 cm in diameter, situated at the anterior part of the knee. Also called the kneecap.
path/o	disease
pathogen	A disease causing microorganism such as bacterium, virus or fungus.
pathologic processes	The abnormal mechanisms and forms involved in the dysfunctions of tissues and organs.
pathological	Pertaining to or caused by disease.
pathology	A medical specialty concerned with the nature of disease and its causes, processes, development, and consequences.
-pathy	disease
patulous	Open or exposed.
Pb	lead
PCA	patient-controlled analgesia
PD	Parkinson disease
PD (2)	pupillary distance
PDA	patent ductus arteriosus
PDR	Physicians' Desk Reference
PE	physical examination
PE (2)	pulmonary embolism
PEA	pulseless electrical activity
peak flow meter	Simple device that allows asthma patients to check lung airflow.
pecten	The middle, narrow zone in the anal canal.
pector/o	chest
pectoral	Relating to the thorax.
pectus carinatum	The chest or breast.
ped/o	child, foot
pediatrics	A medical specialty concerned with maintaining health and providing medical care to children from birth to adolescence.
pediculosis	Head lice.
pedophilia	An adult abnormal attraction to children for sexual purposes.
peduncle	A stalk like structure that serves as a support or connection.
PEEP	positive end expiratory pressure
PEFR	peak expiratory flow rate
PEG	percutaneous endoscopic gastrostomy
pellagra	A disease characterized by scaly dermatitis, diarrhea and dementia caused by a deficiency of niacin and protein in the diet.
pellicle	A thin skin, film or organic membrane
pelv/i	pelvis
pelvic floor	The connective tissues and muscles that lie beneath and support the perineum and pelvis. It extends between the pubic bone anteriorly and the coccyx posteriorly.
pelvis	The lower portion of the trunk, bounded anteriorly and laterally by the two hip bones and posteriorly by the sacrum and coccyx.
pemphigus	Any of several rare diseases characterized by groups of itching blisters.
-penia	deficiency
penicillin	Any of a group of antibiotics derived from cultures of the mold like fungi Penicillium or produced synthetically.
penis	The external reproductive organ of males.
penta-	five
-pepsia	digestion
peptic ulcer	Ulcer that occurs in the regions of the gastrointestinal tract which come into contact with gastric juice.
peptides	Members of the class of compounds composed of amino acids joined together by peptide bonds between adjacent amino acids into linear, branched or cyclical structures.
perception	The process by which the nature and meaning of sensory stimuli are recognized and interpreted.
percussion	Act of striking a part with short, sharp taps in diagnosing the condition beneath the sound obtained.
percutaneous	Through the skin.
perforation	Abnormal opening in a hollow organ or viscus.
performance anxiety	Anxiety related to the execution of a task, especially with an audience.
perfusion	Delivery of blood to the capillaries.
peri-	around, surrounding
periapical	Around an apex, especially the apex of a root of a tooth.
periarthritis	Inflammation of the tissues around a joint capsule.
pericardi/o	pericardium
pericardial effusion	Fluid accumulation within the pericardium. Severe cases can lead to cardiac tamponade.
pericardial fluid	Watery fluid produced in the serous and visceral pericardium surrounding the surface of the heart
pericardial friction rub	An extra heart sound that resembles squeaky leather. May be heard in pericarditis.
pericardiocentesis	Puncture and aspiration of fluid from the pericardium.
pericarditis	Inflammation of the pericardium, caused by infection, injury, or drugs.
pericardium	A thin layered sac enclosing the heart. Fluid between the layers lubricates the constantly moving surfaces.
pericoronitis	Inflammation of the gingiva surrounding the crown of a tooth.
perihepatitis	Inflammation of the peritoneal capsule of the liver
perimenopause	The period of time before menopause when a woman's body changes.
perimetritis	Inflammation of the peritoneal covering of the uterus
perinatal	Pertaining to the period three months before to one month after birth.
perine/o	perineum (surface region in both males and females between the pubic symphysis and the coccyx)
perinephritis	Inflammation of the connective and adipose tissues surrounding the KIDNEY.
perineum	The body region lying between the genital area and the anus on the surface of the trunk, and to the shallow compartment lying deep to this area that is inferior to the pelvic diaphragm. The surface area is between the vulva and the anus in the female, and between the scrotum and the anus in the male.
periodontal	Around a tooth.
periodontics	A dental specialty concerned with the histology, physiology, and pathology of the tissues that support, attach, and surround the teeth, and of the treatment and prevention of disease affecting these tissues.
periodontitis	Inflammation and loss of connective tissues supporting or surrounding the teeth.
periorbital edema	A condition in which the tissues around the eyes become swollen. Puffy eyes.
periosteum	Thick, fibrous membrane covering the surface of a bone except its articular cartilage and areas where it attaches to tendons and ligaments.
periostitis	Inflammation of the periosteum.
peripartum period	The period shortly before, during, and immediately after giving birth.
peripheral neuropathy	Dysfunction of peripheral nerves which can impair movement, sensation and organ function.
periphlebitis	Inflammation of the tissues around a vein
peristalsis	A movement, caused by sequential muscle contraction, that pushes the contents of the intestines or other tubular organs in one direction.
peritone/o	peritoneum (serous membrane lining the abdominal cavity)
peritoneal absorption	Uptake of substances from the peritoneal cavity.
peritoneal cavity	The space enclosed by the peritoneum. It is divided into two portions, the greater sac and the lesser sac or omental bursa, which lies behind the STOMACH. The two sacs are connected by the foramen of Winslow, or epiploic foramen.
peritoneal dialysis	Dialysis fluid being introduced into and removed from the peritoneal cavity.
peritoneum	The serous membrane that lines the walls of the abdominal cavity and folds inward to enclose the viscera.
peritonitis	Inflammation of the peritoneum lining the abdominal cavity as the result of infectious, autoimmune, or chemical processes.
perleche	Fissures and cracks at the corner of the mouth
permeability	Property of membranes and other structures to permit the passage of substances, heat and light.
pernicious	Diseases that are highly dangerous or fatal.
pernicious anemia	Vitamin B12 deficiency anemia. A type of megaloblastic anemia.
pero-	deformed
peroneal	Pertaining to the fibula.
PERRLA	pupils equal, regular, react to light and accommodation
pertussis	Whooping cough. Contagious bacterial infection of the upper respiratory tract. Cold-like symptoms followed by many weeks of coughing. Preventable with immunization.
pest/i	pests, plague
pesticide	A substance used to destroy pests.
PET	positron emission tomography
-petal	moving forward
petechia	A small, round, dark-red spot caused by intradermal or submucous hemorrhage.
petechiae	Tiny flat round red spots under the skin surface caused by intradermal hemorrhage. Spots do NOT blanch with pressure.
petr/o	stone, stone-like hardness
-pexy	surgical fixation
Peyronie disease	A condition where plaques form under the skin of the penis, causing the penis to bend.
PFT	pulmonary function test
PH	past medical history
phac/o	pertaining to lens
phag/o	eat, swallow
-phagia	eating, swallowing
phagocytosis	The engulfing and degradation of microorganisms.
-phagy	eating, devouring
phak/o	pertaining to lens
phalanges	Fingers or toes
phalangitis	Inflammation of a finger or toe.
phall/o	penis
phantom limb	Phantom sensations that occur following the complete or partial loss of a limb.
Pharm	pharmacy
pharmac/o	drugs
pharmacology	The study of the origin, nature, properties, and actions of drugs and their effects on living organisms.
pharmacy	The art and the facility for the preparation and dispensing of drugs.
pharyng/o	throat
pharyngeal	Of, or pertaining to, or coming from the pharynx.
pharyngitis	Sore throat. Inflammation of the throat.
pharynx	The throat. A fibromuscular tube that conducts air to the larynx and lungs and food to the esophagus.
phas/o	speech
-phasia	speech
phenol	A strong disinfectant.
phenotype	The outward appearance of the individual.
phenylketonuria	Any of a group of autosomal recessive disorders of the ability to metabolize phenylalanine.
-pheresis	removal
pheromones	Chemical substances, excreted by an organism into the environment, that elicit behavioral or physiological responses from other organisms of the same species.
-phil	attraction
phil/o	attraction
-philia	affinity for
phimosis	A condition of a narrowed or tightened foreskin that cannot be retracted to reveal the glans penis.
phleb/o	vein
phlebitis	Inflammation of a vein, commonly a vein in the leg.
phlebo-	vein
phlebography	An invasive imaging study of leg veins with a contrast agent injects using a catheter. Phlebography is the most accurate test for detecting deep vein thrombosis.
phlebotomy	The techniques used to draw blood from a vein for diagnostic purposes.
phlegm	Mucus in the respiratory airways (trachea, bronchial tree).
phob/o	fear, adversion
-phobia	abnormal fear
phon/o	sound, voice
phonation	To vocalize.
phonocardiogram	A waveform of heart sound amplitude over time, usually a few heartbeats.
phor/o	to carry
-phore	carrier, processor
phot/o	light
photalgia	Pain in the eye causes by bright light.
photophobia	Abnormal sensitivity to light.
photoreceptor cells	Specialized cells that detect and transduce light.
photoretinitis	Injury to the retina of the eye caused by looking directly into the sun without protection.
photosynthesis	The synthesis by organisms of organic compounds, especially carbohydrates, from carbon dioxide using energy obtained from light .
phototherapy	Treatment of disease by exposure to light, especially by specific wavelengths.
phototrophic	Capable of deriving energy from light.
phreni-	diaphragm, mind
phrenic	Pertaining to the diaphragm.
phyl/o	race, species, type
-phylaxis	protection
phyllo-	leaf
physi-	physical, natural
physiatrist	A doctor specializing in the physiological treatment of patients with conditions affecting movement. Often used in stroke rehabilitation.
physical examination	Systematic and thorough inspection of the patient for physical signs of disease or abnormality.
physicians	Individuals licensed to practice medicine.
-physis	growth, growing
physo-	swelling, gas
phyt-	plants
PI	present illness; previous illness
pico-	one trillionth
PID	pelvic inflammatory disease
-piesis	pressure
piez/o	pressure
pigmentation	Coloration or discoloration of a part by a pigment.
PIH	pregnancy-induced hypertension
pil/o	hair
piloerection	The standing up of hairs on the skin
pilonidal sinus	A hair-containing cyst or sinus, occurring chiefly in the coccygeal region.
pineal gland	A light-sensitive neuroendocrine organ attached to the roof of the Third ventricle of the brain. the pineal gland secretes melatonin, other biogenic amines and neuropeptides.
pinta	A contagious bacterial skin disease prevalent in tropical America.
PIP	proximal interphalangeal
pituitar/o	pituitary
pituitary adenoma	Benign epithelia neoplasm of the pituitary.
pituitary gland	A small, oval, unpaired, endocrine gland connected to the hypothalamus by a short stalk which is called the infundibulum. Its secretions control the other endocrine glands and influence growth, metabolism, and maturation.
pityriasis	Any of a group of skin diseases characterized by the formation of fine, branny scales. This term is but only with a modifier.
PKU	phenylketonuria
placebo	Any dummy medication or treatment.
placenta	A vascular organ that develops during pregnancy, lining the uterine wall and partially enveloping the fetus. The placenta produces an array of steroid, protein and peptide hormones .
placenta previa	A condition when the placenta covers part or all of the cervix during the last months of pregnancy.
plagiocephaly	The condition characterized an irregular shape of the head often in parallelogram shape with a flat spot on the back or one side of the head.
plague	An infectious disease transmitted by the bite of a flea from a rodent infected with the bacillus Yersinia pestis.
-plakia	patches
plan/o	flat, plan, level
plani-	flat, level
plantar	Bottom of the foot
plantar fasciitis	Irritation of the connective tissue that runs from the heel to the base of the toes. Also known as :postman's heel".
plaque	Fatty deposits formed on the walls of arteries.
-plasm	formation
plasma	The part of blood which is not blood cells. Blood plasma also contains glucose and other dissolved nutrients. It also helps blood clot.
plasmacytoma	Any discrete, presumably solitary, mass of neoplastic plasma cells either in bone marrow or various extramedullary sites.
plasmapheresis	Procedure whereby plasma is separated and extracted and the red cells returned to the donor.
plasmo-	plasma
plast/o	formation
-plasty	surgical repair
platelets	Part of blood that help stop bleeding by clumping and clotting blood vessel injuries.
platy-	broad, flat
platybasia	A malformation of the cranium so that the floor of the posterior cranial fossa bulges upward in the region about the foramen magnum.
pledget	A small compress used to medicate, protect, or absorb drainage from a wound
-plegia	paralysis
pleocytosis	A presence of an abnormally high number of cells in the cerebrospinal fluid.
pless/i	striking, percussion
pleur/o	pleura, rib
pleura	The membrane enveloping the lungs consisting of two layers. The visceral pleura is attached directly to the lungs. The outer parietal pleura lines the thoracic cavity and diaphragm. Between the two layers is the pleural cavity, containing a lubricating liquid film.
pleural effusion	Excessive fluid in the pleural cavity which may cause breathlessness.
pleural friction rub	Sound created by the rubbing of when the chest wall moves. Stops when patient holds her breath. Often heard with pleurisy. Thick inflamed surfaces sliding by one another.
pleurisy	Inflammation of the pleura, the membranes covering the lungs.
pleurodynia	Inflamed lung membranes causing pain during inhalation.
plexus	A network of nerves or blood vessels.
plic/o	fold
PLT	platelet
pluri-	several, more
PM	afternoon, evening
PMH	past medical history
PMN	polymorphonuclear (neutrophil leukocyte)
PMS	premenstrual syndrome
PND	paroxysmal nocturnal dyspnea
-pnea	breathing
pneo-	air, breath, breathing
pneum/o	lung, air
pneumocephalus	Presence of air or gas within the intracranial cavity usually the result of a fracture.
pneumoconiosis	Occupational lung disease caused by prolonged inhalation of dust. Common lung disease in mining.
pneumocyte	Any of the epithelial cells lining the alveoli of the lung.
pneumon/o	lung
pneumonectomy	Surgical removal of part or all of a lung.
pneumonia	Inflammation of the lungs with alveoli filling with pus. Typically caused by infection and can follow flu, colds and other illnesses.
pneumonitis	Inflammation of lung tissue.
pneumoperitoneum	Presence of air or gas in the peritoneal cavity.
pneumorrhachis	Presence of air or gas within the spinal canal cavity.
pneumothorax	Partial or fully collapsed lung. An accumulation of air in the pleural cavity. Caused by trauma, such as a gun shot or stab wound and can also occur spontaneously.
PNH	paroxysmal nocturnal hemoglobinuria
PNI	peripheral nerve injury
PNS	peripheral nervous system
PO	orally
-pod	foot
pod/o	foot
podiatry	A medical specialty concerned with the diagnosis and treatment of foot disorders and injuries.
-poiesis	production, formation
poikil-	irregular, varied
poison	A substance capable of damaging the structure or function of the body.
polio-	gray
poliomyelitis	A highly infectious viral disease that involves the gray matter of the spinal cord, leading to paralysis, muscular atrophy, and deformity.
poly-	many
polyarthritis	Simultaneous inflammation of several joints.
polychondritis	Inflammation of cartilage.
polycystic kidney disease	An inherited disease in which cysts develop within the kidneys.
polycystic ovary syndrome	A condition in which a woman’s levels of the sex hormones estrogen and progesterone are out of balance. Often cause for infertility
polycythemia	Abnormal increase in the aggregate red cell mass of the blood.
polydactyly	A congenital anomaly of the hand or foot, characterized by supernumerary digits.
polydipsia	Excessive thirst.
polymorphism	Occurring in several different forms.
polymyositis	Inflammation of the muscles or associated tissues, such as the blood vessels that supply the muscles
polyneuropathy	A disease of multiple peripheral nerves simultaneously.
polyp	Abnormal tissue mass that protrudes into the lumen of the digestive or respiratory tracts.
polyphagia	Excessive hunger or appetite.
polyps	Discrete abnormal tissue masses that protrude into the lumen of the digestive tract or the respiratory tract.
polysomnography	Sleep study. Includes monitoring of respiratory patterns, brain waves, sleep stages, and other physiological variables.
polyuria	Excessive production of urine.
pono-	fatigue, exhaustion, overwork
pons	The front part of the hindbrain that lies between the medulla and the midbrain ventral to the cerebellum, serving as a relay station for neural pathways.
popliteal	Pertaining to the area behind the knee.
por/o	passage, opening, duct
porokeratosis	A rare, chronic, progressive autosomal dominant skin disorder market by craterlike patches.
poroma	A neoplasm of cells lining the skin openings of sweat glands.
-porosis	decrease in density
portal vein	A vein that conducts blood from the digestive organs, spleen, pancreas, and gallbladder to the liver.
-posia	drinking, fluid intake
posset	A small amount of milk that is regurgitated by infants after feeding.
post-	after, behind, back
post-traumatic stress disorder	A disorder that develops in people who have experienced a terrifying event.
post.	posterior
posterior	back
postmenopause	The physiological period following the menopause.
postpartum	The period that is shortly after giving birth.
postprandial	After a meal.
posture	The position of the body.
ppm	parts per million
PR	through the rectum
-prandial	meal
-praxia	to perform, action
PRBC	packed red blood cells
pre-	before, in front of
prebiotics	Indigestible food ingredients that promote overall health by supporting the activity of probiotic bacteria in the large intestine.
precordium	The region of the thorax immediately over the heart.
prediabetes	A condition in which blood glucose levels are higher than normal. Considered a warning sign for diabetes.
prediabetic	The time period before the development of symptomatic diabetes mellitus.
preeclampsia	A serious pregnancy disorder characterized by high blood pressure, a large amount of protein in the urine and edema of hands and feet.
pregnancy	Carrying developing offspring (embryos or fetuses) in utero before birth.
preleukemia	Conditions in which the abnormalities in the peripheral blood or bone marrow represent the early manifestations of acute leukemia, but in which the changes are not of sufficient magnitude or specificity to permit a diagnosis of acute leukemia by the usual clinical criteria.
premature ejaculation	The emission of semen and seminal fluid during the act of preparation for sexual intercourse, i.e. before there is penetration, or shortly after penetration.
premedication	Preliminary administration of a drug preceding a diagnostic, therapeutic, or surgical procedure.
premenopause	The period before menopause. The transition from full sexual maturity to cessation of ovarian cycle takes place between the age of late thirty and early fifty.
preneoplastic	Preceding the formation of a tumor.
prepuce	The fold of skin that grows over the end of the penis.
presby/o	old age
presbycusis	Hearing loss that gradually occurs in most individuals as they grow older.
presbyopia	An age-related condition when the eye's lens doesn't change shape as easily as it once did
pressure ulcer	An ulcer that appears in the skin over a bony prominence due to compression and inadequate blood perfusion. Bedridden or chair bound patients are at risk. Also called bedsore.
prevalence	A measure of morbidity based on currents levels of a disease in a population.
priapism	A abnormally prolonged erection of the penis.
primi-	first
primigravida	A woman who is pregnant for the first time.
primipara	A woman who has given birth to one viable infant.
prion	A small infectious protein particle causing neurodegenerative diseases including Creutzfeldt-Jakob syndrome.
PRL	prolactin
pro-	before, in front of
probability	The likelihood that an event will occur.
proct/o	anus and rectum
proctocolitis	Inflammation of the rectum and the colon.
proctoscope	Endoscope for examination of the rectum and anus.
prodrome	An early symptom that precedes the onset of disease.
profunda	Blood vessels situated deep in the body tissues they supply.
progeria	An abnormal congenital condition of premature aging.
progesterone	A sex hormone produced by the ovaries.
prognosis	A prediction of a outcome of a disease.
projection	A defense mechanism, operating unconsciously, whereby that which is emotionally unacceptable in the self is rejected and attributed (projected) to others. Also called the blaming mechanism.
prokaryote	A unicellular organism lacking a true nucleus and nuclear membrane, having genetic material consisting of a single molecule of double-stranded DNA.
prolactin	A pituitary hormone that stimulates and maintains lactation in postpartum mammals.
prolactinoma	A begin tumor of the pituitary gland overproduces a hormone called prolactin.
prolapse	The protrusion or sinking down of an organ or part of an organ.
promontory	A projecting part.
pronation	The inward roll of the foot (medial malleolus) while walking or running.
prone	Lying on the abdomen
prone position	The posture of an individual lying face down.
proptosis	Protrusion or bulging of the eye.
pros/o	forward, anterior
prosop/o	face
prospective study	A forward looking study of a group over a long period.
prostat/o	prostate
prostate	A gland that is part of a male reproductive system. Located below the bladder.
prostatic neoplasms	Tumors or cancer of the prostate.
prostatism	Lower urinary tract symptom, such as slow urinary stream, associated with prostatic hyperplasia in older men.
prostatitis	Inflammation of the prostate gland.
prosthesis	A device that replaces a missing body part or makes a part of the body work better.
prote/o	protein
protein	A large molecule consisting of a long chain or sequence of amino acids that is an essential constituent of the body.
proteinuria	The presence of proteins in the urine, an indicator of kidney diseases.
proteolysis	The decomposition of proteins into peptides and amino acids by enzymes in the digestive tract.
proto-	first
protoplasm	The living contents of a cell
protozoa	An animal subkingdom, comprised of primitive, single-celled, microscopic animals able to move by amoeboid action or by means of cilia or flagella. Many protozoa are parasitic on humans.
prox.	proximal
proxim/o	nearest
proximal	Nearest to the point of attachment to the trunk
proxy	A person authorized to decide or act for another person, for example, a person having durable power of attorney.
prurigo	A chronic inflammation of the skin characterized by a persistent eruption of papules that itch intensely.
pruritus	Itch.
pruritus vulvae	Itching of the vulva.
psamm/o	sand
pseud-	false
pseudarthrosis	A new, false, fibrous joint arising at the site of an ununited fracture.
pseudo-	false
pseudophakia	Presence of an intraocular lens after cataract extraction.
psi	pounds per square inch
psor/o	itching
psoriasis	A skin disease that causes itchy patches of thick, red skin with silvery scales on the scalp and flexor joint surfaces.
psoriatic arthritis	Arthritis associated with psoriasis, affecting joints and the spine.
PSV	pressure supported ventilation
PSVT	paroxysmal supraventricular tachycardia
psych/o	mind
psychiatry	The medical specialty that deals with the diagnosis, prevention and treatment of mental disorders.
psychology	The science dealing with the study of mental processes and behavior in man and animals.
psychosis	A condition characterized by a loss of contact with reality.
psychotherapy	A general term for the treatment of mental illness or emotional disturbances.
PT	physical therapy
PTCA	percutaneous transluminal coronary angioplasty
-pterygium	abnormality of conjunctiva
PTH	parathyroid hormone
ptosis	Drooping of the upper eyelid.
-ptosis	drooping, prolapse
PTSD	post traumatic stress disorder
PTT	partial thromboplastin time
PTX	pneumothorax
ptyal/o	saliva
-ptysis	spitting
pub/o	pubic, pubes
puberty	Becoming first capable of reproducing sexually.
pubic bone	A bone that forms the lower and anterior part of each side of the hip bone.
pubic symphysis	A slightly movable cartilaginous joint which occurs between the pubic bones.
PUD	peptic ulcer disease
pudendal nerve	A nerve which originates in the sacral spinal cord (S2 to S4) and innervates the perineum, the external genitalia, the external anal sphincter and the external urethral sphincter. Can be damaged in childbirth.
puerperal	The period up until six to eight weeks after childbirth.
pulm/o	lung
pulmon/o	lung
pulmonary	Pertaining to the lungs.
pulmonary artery	The short wide vessel that moves blood from the right ventricle to the lungs.
pulmonary circulation	The circulation of the blood to and through the lungs
pulmonary edema	Excessive accumulation of fluid in the lung. Can be life-threatening. Often associated with heart failure.
pulmonary embolism	A clot blocking of the pulmonary artery or one of its branches.
pulmonary fibrosis	Progressive formation of fibrotic (scar) tissue in the lungs. Patients show increasing dyspnea.
pulmonary function test	A battery of tests that evaluate the volume and flow rate of air in and out of the lungs.
pulmonary infarction	necrosis of lung tissue that is cause by the lack of oxygen or blood supply. The most common cause of pulmonary infarction is a blood clot in the lung.
pulmonary valve	The heart valve at the intersection of the right ventricle and the pulmonary artery.
pulmonary valve regurgitation	Back flow of blood from the pulmonary artery into the right ventricular due to a leaky pulmonary valve.
pulmonary valve stenosis	The pathologic narrowing of the pulmonary valve opening. Limits blood flow from the right ventricle to the pulmonary artery.
pulmonary veins	The veins that return the oxygenated blood from the lungs to the left atrium of the heart.
pulmonologist	An internal medicine specialist concerned with the diagnosis and treatment of diseases and defects of the lungs and bronchial tree.
pulp	A soft mass of tissue.
puls/o	beating, to beat
pulse	The rhythmical expansion and contraction of an artery, caused by blood pumping from the heart.
pulse oximeter	Device that measures oxygen saturation in the blood.
-puncture	to pierce a surface
pupil	The aperture in the iris through which light passes.
pupill/o	pupil
purkinje fibers	Cardiac muscle fibers that conduct the cardiac impulse from the atrioventricular node to the ventricles causing them to contract.
purpur/o	purple
purpura	Blood spots on the skin that are purple-colored, between 4-10 mm resembling bruising.
purul/o	pus formation
purulent	Pertaining to pus.
PUVA	psoralen ultraviolet A
PVC	premature ventricular contraction
py/o	pus
pyarthrosis	Acute inflammation of synovial membranes.
pyel/o	renal pelvis
pyelectasis	Dilation of the pelvis of the kidney.
pyelitis	Inflammation of the renal pelvis.
pyelocystitis	Inflammation of the kidney pelvis and the urinary bladder.
pyelonephritis	Inflammation of the kidney involving the renal parenchyma (the nephrons), kidney pelvis and kidney calices. It is characterized by abdominal pain, fever, nausea, vomiting and occasionally diarrhea.
pyg/o	buttocks
pykn/o	thick, dense, compact
pyl/e	portal vein
pylethrombosis	Thrombosis of the portal vein.
pylor/o	pylorus (opening between the stomach and duodenum)
pylorus	The region of the stomach at the junction with the duodenum.
pyoderma	Any purulent skin disease.
pyogenic	Producing pus.
pyometra	Accumulation of pus in the uterine cavity.
pyomyositis	An acute, intramuscular suppuration of the large skeletal muscle groups.
pyonephrosis	Distention of kidney with the presence of pus and destruction of the renal parenchyma. It is often associated with renal obstruction and can lead to total or nearly total loss of renal function.
pyr/o	fire, fever
pyret/o	fever
pyrex/o	fever
pyrosis	Substernal pain or burning sensation, usually associated with regurgitation of gastric juice into the esophagus. Also called heartburn.
pyuria	White blood cells or pus cells in the urine.