Word Part | Definition |
N&V | nausea and vomiting |
Na | sodium |
NAD | no acute distress |
nails | The thin, translucent, horny plates that cover the dorsal surfaces of the distal phalanges of the fingers and toes |
nano- | one-billionth, dwarfism |
nanospheres | Spherical particles of nanometer dimensions. |
narc/o | sleep, numbness, stupor |
narcissism | Excessive admiration of self. |
narcolepsy | A chronic brain disorder that involves poor control of sleep-wake cycles. |
narcotics | Agents that dull the sense of pain and cause somnolence. They are comprised of natural or synthetic derivatives of opium or morphine or any substance that has such effects. |
nares | An external opening in the nasal cavity. A nostril. |
nas/o | nose |
nasal cavity | The proximal portion of the respiratory passages on either side of the nasal septum. On inhalation the air is warmed, moistened, smelled and filtered. |
nasal decongestants | Drugs designed to treat inflammation of the nasal passages. |
nasal lavage | Irrigation of the nose with saline or irrigation solutions to remove irritants, allergens or microorganisms from the nose. |
nasal septum | The partition separating the two nasal cavities in the midplane. |
nasion | A point on the skull where the top of the nose meets the ridge of the forehead. |
nasolacrimal duct | A tubular duct that conveys tears from the lacrimal gland to the nose. |
nasopharynx | The top portion of the pharynx situated posterior to the nose and superior to the soft palate. |
nat/o | birth |
natal | Relating to birth. |
natr/o | sodium |
nausea | An unpleasant sensation in the stomach accompanied by the inclination to vomit. |
NCI | National Cancer Institute |
NDC | National Drug Code |
nebulizers | Devices that create an aerosol a mist (vapor). It is used to administer drugs or to humidify air. |
neck | The body part connecting the head to the rest of the body. |
necr- | death, corpse |
necrobiosis | The natural death of cells due to age, use or development. |
necrobiotic disorders | A group of disorders characterized by swelling, basophilia, and distortion of collagen bundles in the dermis. |
necrosis | Pathological cell or tissue death, caused by damage, trauma, ischemia or infection. |
necrotizing fasciitis | A rare but serious infection caused by bacteria. It destroys skin, fat and tissue covering muscles. |
needle sharing | Usage of a single needle among two or more people for injecting drugs, a high-risk behavior for contracting infectious disease. |
negativism | Behavior marked by extreme skepticism and persistent resistance to external advice. |
nemosis | The process of cell activation and death in fibroblasts. |
neo- | new |
neocortex | The largest portion of the cerebral cortex, the outer surface of the cerebrum, responsible for spatial reasoning, thought, language, memory and sensory perception. |
neonatal | Pertaining to a new baby, for the first 28 days after birth. |
neonate | An infant less than one month old. |
neoplasia | The formation of a neoplasm |
neoplasm | An abnormal new growth of tissue. Also called a tumor. |
neovascularization | Formation of new blood vessels. |
nephr/o | kidney |
nephralgia | Pain in the kidney. |
nephrectomy | Excision of kidney. |
nephritis | Inflammation of any part of the kidney. |
nephrolithiasis | Formation of kidney stones. |
nephrology | A subspecialty of medicine concerned with the kidney. |
nephron | Very small filtering structures in the kidneys. |
nephrosclerosis | Hardening of the kidney due to infiltration by fibrous connective tissue. Usually caused by chronic hypertension. |
nephrosis | Any degenerative disease of the kidney. |
nephrotic syndrome | Disease of the kidney without inflammatory or neoplastic components. |
nerve | A cordlike structure of the body, comprising a collection of conducting fibers that convey impulses between a part of the central nervous system and another body region. |
nerve block | Interruption of neural conduction in peripheral nerves or nerve trunks by the injection of a local anesthetic agent. |
neur/o | nerve |
neural conduction | The propagation of the nerve impulse along the nerve away from the site of an excitation stimulus. |
neuralgia | Intense pain that occurs along the course of a peripheral or cranial nerve. |
neurapraxia | A peripheral nerve injury marked by a temporary loss of conduction of impulses. |
neurasthenia | A mental disorder characterized by chronic fatigue and concomitant physiologic symptoms. |
neuri- | nerve, nervous system |
neuritis | A general term indicating inflammation of a nerve, often marked by pain, numbness or tingling, or paralysis. |
neurocytoma | A brain tumor of undifferentiated cells of nervous origin. |
neurodermatitis | An extremely variable eczematous skin disease that is presumed to be a response to prolonged vigorous scratching, rubbing, or pinching to relieve intense pruritus. |
neuroendocrine | Pertaining to the relationships between the nervous and endocrine systems |
neuroendocrinology | The study of the relationships between the nervous system and the endocrine system. |
neurofibroma | A moderately firm, benign, encapsulated tumor resulting from proliferation of Schwann cells and fibroblasts that includes portions of nerve fibers. |
neurofibrosarcoma | A malignant tumor that arises from small cutaneous nerves, is locally aggressive, and has a potential for metastasis. |
neurogenesis | Formation of neurons which involves the differentiation and division of stem cells in which one or both of the daughter cells become neurons. |
neuroglia | The supportive tissue of the nervous system |
neurological | Pertaining to the nervous system |
neurology | A medical specialty concerned with the study of the structures, functions, and diseases of the nervous system. |
neuroma | A benign neoplasm composed of nerve cells and nerve fibers. |
neuromuscular | Disorders that affect the nerves that control voluntary muscles. |
neuron | The basic cellular unit of nervous tissue. Each neuron consists of a body, an axon, and dendrites. Their purpose is to receive, conduct, and transmit impulses in the nervous system. |
neuroretinitis | Inflammation of the optic nerve and retina. |
neurotransmitters | Chemical messengers that carry signals to other cells in the body. |
neurotropic | Having an affinity for the nervous system or the growth of neural tissue. |
neutr/o | neutral |
neutropenia | Abnormally decrease in the numbers of neutrophils in circulating blood. |
neutrophils | A type of white blood cell that is an early responder to infections. |
nev/o | mole, birthmark |
nevus | A malformation of skin that is present at birth, including moles and birthmarks. |
NG | nasogastric |
NGF | nerve growth factor |
niacin | A water-soluble vitamin B complex. |
nicotine | A highly toxic alkaloid. |
nictation | A reflex that closes and opens the eyes rapidly. Blinking. |
NICU | neonatal intensive care unit |
NIDDM | noninsulin-dependent diabetes mellitus |
night blindness | Failure or reduced ability to see in dim light. |
night terrors | A sleep disorder characterized by episodes of abrupt awakening suggesting extreme fright. This condition primarily affects children and young adults. |
NIH | National Institutes of Health |
nipple | The conic projection on the breast which provides an outlet for milk from the mammary glands. |
nitrogen | An element with the atomic symbol N, atomic number 7, comprising 78% of the earth's atmosphere by volume. |
nitroglycerin | A vasodilator which relieves angina pectoris. |
NK | natural killer |
NKA | no known allergies |
NMJ | neuromuscular junction |
nocebo effect | A negative placebo effect. |
noct/i | night |
nocturia | Patient needs to wake at night to pass urine. |
nocturnal enuresis | Involuntary discharge of urine during sleep at night after expected age of completed development of urinary control. |
nocturnal myoclonus | A sleep disorder where the patient moves involuntarily during sleep. Also called periodic limb movement disorder. |
nod/o | knot |
-noia | mind, will |
nomen- | name, pertaining to names |
non- | not |
norepinephrine | A neurotransmitter that is secreted in response to stress, increasing blood pressure and glucose. |
norm- | normal |
normotensive | Having normal blood pressure. |
norovirus | A virus associated with epidemic gastroenteritis. |
nos- | disease |
nose | A part of the upper respiratory tract. It includes the external nose, the nasal cavity, and the paranasal sinuses. |
nosocomial pneumonia | Pneumonia acquired during a hospital stay. |
nostrums | Medicines whose effectiveness is unproven and whose ingredients are often secret. A quack remedy. |
noto- | back |
noxae | Anything harmful to the body. |
NP | nurse practitioner |
NPN | nonprotein nitrogen |
NPO | nothing by mouth |
NS | normal saline |
NSAID | nonsteroidal anti-inflammatory drug |
NSR | normal sinus rhythm |
NTD | neural tube defect |
nucle/o | nucleus |
nucleic acid | Any of a group of long, linear macromolecules, either DNA or various types of RNA, that carry genetic information. |
nucleotides | The base units of nucleic acids. |
nucleus | The part of a cell that contains DNA and RNA. |
nulli- | none |
nulligravida | A woman who has never been pregnant. |
nullipara | A woman who has never borne a child. |
nutation | The act of nodding one's head, especially involuntarily. |
nutri/o | to nourish |
nyct/o | night, darkness |
nyctalopia | Night blindness. |
nystagmus | A vision condition in which the eyes make repetitive, uncontrolled movements, usually side to side. |