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Medical Dictionary: r

Word	Definition
R/O	rule out
Ra	radium
rabies	Acute viral infection affecting mammals, including humans.
rachi/o	spinal column
rad	radiation absorbed dose
RAD (2)	right anterior descending
radi/o	x-rays, radius
radial artery	An artery in the forearm that starts at the bifurcation of the brachial artery and passing in branches to the forearm, wrist, and hand.
radial keratotomy	A surgical procedure used to decrease nearsightedness.
radial nerve	A major nerve of the upper extremity, originating in the lower cervical and upper thoracic spinal cord, traveling via the posterior cord of the brachial plexus, and supplying motor innervation to extensor muscles of the arm and cutaneous sensory fibers to extensor regions of the arm and hand.
radiation	Electromagnetic energy that travels through empty space with the speed of light.
radicul/o	nerve root
radicular cyst	A slow growing cyst of the periodonal tissue at the root of a tooth.
radiculopathy	Disease involving a spinal nerve root.
radiography	Examination of any part of the body for diagnostic purposes by means of X-rays or gamma rays.
radioisotopes	Isotopes that exhibit radioactivity.
radiology	A medical specialty concerned with the use of x-ray and other forms of radiant energy in the diagnosis and treatment of disease.
ram/i	branch
ramus	A branch, as of a nerve, blood vessel or bone.
ranula	A cyst found on the floor of the mouth. Also called sublingual cyst.
rape	Sexual intercourse without consent of the victim.
rash	A temporary eruption of spots on the skin.
rationalization	An unconscious defense mechanism in which a person attempts to justify behavior while ignoring the real reasons.
Raynaud disease	An idiopathic vascular disorder of small arteries and arterioles.
RBBB	right bundle branch block
RBC	red blood cell; red blood count
RDA	recommended daily/dietary allowance
RDS	respiratory distress syndrome
Re	rhenium
re-	again, back
-receptor	receiver
recessive	Describing a gene capable of producing its characteristic phenotype in the organism only when its allele is identical.
rect/o	rectum
rectocele	Herniation of the rectum into the vagina.
rectum	The distal segment of the large intestine, between the sigmoid colon and the anal canal.
recurrence	The return of a sign, symptom, or disease after a remission.
referred pain	Pain felt at a place in the body different from the injured or diseased part.
reflex	A quick, involuntary movement or exercise of function, in response to a stimulus applied to the periphery and transmitted to the brain or spinal cord.
reflex arc	The neural path of a reflex.
regimen	A systematic plan for therapy, often involving diet, exercise and medication.
regurgitation	The return of partly digested food from the stomach to the mouth. Also, the backflow of blood past an abnormal heart valve.
rejuvenation	The restoration of youthfulness, vitality, and freshness.
relapse	The return of disease symptoms after partial recovery.
REM	rapid eye movement
rem sleep	A stage of sleep characterized by rapid eye movements and low voltage fast pattern EEG. It is usually associated with dreaming.
remission	The abatement or disappearance of a disease as a result of treatment.
ren/o	kidney
renal	Pertaining to the kidneys.
reperfusion	Restoration of blood supply to tissue which was ischemic.
replication	The process by which double-stranded DNA makes copies of itself when the cell divides.
resection	Surgical removal of all or part of a structure, organ or tissue.
residual volume	The volume of air remaining in the lungs at the end of a maximal expiration.
respir/o	breathing
respiration	Breathing.
respiratory system	The organs and structures that bring about gas exchange between ambient air and the blood.
respiratory therapy	Care of patients with abnormalities associated with the pulmonary system.
restenosis	The recurrence of stenosis in an artery after previous treatment.
resuscit/o	revive
resuscitation	To restore consciousness or other signs of life to one apparently dead.
rete	A network of blood vessels, fibers or nerves.
retention	The ability of the digestive system to hold fluids and food.
RETIC	reticulocyte
reticul/o	net, network
reticulocytes	Immature erythrocytes.
reticulocytosis	An increase in circulating reticulocytes, which is among the simplest and most reliable signs of accelerated erythrocyte production.
retin/o	retina
retina	The ten-layered nervous tissue membrane of the eye. The innermost layer of the eye, which receives images transmitted through the lens and contains the receptors for vision, the rods and cones
retinitis	Inflammation of the retina.
retinopexy	A surgery for certain types of retinal detachments.
retractor	A surgical instrument used to draw aside and hold the edges of a wound or structures.
retro-	backward
Reye syndrome	An acquired encephalopathy of young children that follows an acute febrile illness, usually influenza or varicella infection.
RF	rheumatoid factor
Rh	rhesus factor
rh factor	A type of protein on the surface of red blood cells. Most people who have the Rh factor are Rh-positive. Those who do not have the Rh factor are Rh-negative.
rhabd-	rod
rhabdomy/o	striated muscle
rhabdomyoma	A rare, benign neoplasm derived from striated muscle.
rhabdomyosarcoma	Malignant neoplasm derived from skeletal (striated) muscle.
RHD	rheumatic heart disease
rhe/o	stream, flow, electric current
rheumatic diseases	Disorders of connective tissue, especially the joints and related structures, characterized by inflammation, degeneration, or metabolic derangement.
rheumatic fever	A disease occurring as a complication of inadequately treated strep throat infection. Can result in serious damage to heart valves.
rheumatoid arthritis	An autoimmune disease that causes pain, swelling, and stiffness in the joints, commonly the hands and wrists. May lead to early crippling.
rheumatology	A subspecialty of medicine concerned with the study of inflammatory or degenerative processes and metabolic derangement of connective tissue structures which pertain to a variety of musculoskeletal disorders, such as arthritis.
rhin/o	nose
rhinitis	Inflammation of the nasal mucous membrane.
rhinomanometry	Technique for measuring airflow and pressure in the nasal cavity during respiration.
rhinoplasty	Plastic surgery on the nose.
rhinosporidiosis	Chronic, localized fungal infection of mucocutaneous tissues, especially the nose.
rhiz/o	root
rhodo-	red
rhonchi	A coarse rattling breath sound somewhat similar to snoring.
rhythm/o	rhythm
rhytid/o	wrinkle
rhytidectomy	A facelift.
rhytidoplasty	Plastic surgery performed for the elimination of skin wrinkles.
riboflavin	Vitamin B2.
ribs	The flat, curved bones that form a protective cage for the chest organs, consisting of twelve curved bones which connect to the vertebral column posteriorly and terminate anteriorly as costal cartilage.
RICE	rest, ice, compression, elevation
rickets	A disease of growing bone caused by interruption of bone mineralization. Caused by lack of vitamin D.
rickettsia	A genus of gram-negative, aerobic, rod-shaped bacteria often surrounded by a protein micro capsular layer and slime layer. Transmitted to humans by arthropods. Cause Lyme Disease, Rocky Mountain Spotted Fever, Typhus.
rigor mortis	Muscular rigidity which develops in the cadaver usually from 4 to 10 hours after death and lasts 3 or 4 days.
RIND	reversible ischemic neurologic deficit
RLE	right lower extremity
RLL	right lower lobe
RLQ	right lower quadrant
RML	right middle lobe of lung
Rn	radon
rna	Any of a class of nucleic acids that can encode genetic information and play an essential role in protein synthesis.
RNP	Registered Nurse Practitioner
ROM	range of motion
ROS	review of systems
rosacea	A common, chronic skin condition characterized by facial redness and often small, red pus-filled bumps. Also known as "Adult Acne".
rot-	wheel, turn
rotator cuff	The musculotendinous sheath formed by the supraspinatus, infraspinatus, subscapularis, and teres minor muscles. These help stabilize the head of the humerus in the glenoid fossa and allow for rotation of the shoulder joint about its longitudinal axis.
RPh	Registered Pharmacist
RPM	revolutions per minute
RQ	respiratory quotient
RR	recovery room
RR (2)	respiratory rate
-rrhage	bursting forth
-rrhaphy	suture
-rrhea	discharge, flow
-rrhexis	rupture
RSI	repetitive stress injury
RSV	respiratory syncytial virus
RT	Respiratory Therapist
rubella	Infectious viral disease caused by virus entering the respiratory tract and spreading to the lymphatic system. Often affecting children and nonimmune young adults. High risk of deafness in fetus. Preventable with MMR vaccine.
RUE	right upper extremity
RUL	right upper lobe
rupture	Forcible or traumatic tear of an organ or other soft part of the body.
RUQ	right upper quadrant
RV	residual volume
Rx	prescription, medication