Dictionary

Body systems

Anatomy and the conditions of each body system, from the heart and lungs to the skin.

mucous membraneThe moist lining of body openings and passages, such as the mouth, nose, eyelids, gut and airways.

mucusThe thick, slippery fluid made by mucous membranes that moistens and protects them.

multiple myelomaA cancer of plasma cells, the white blood cells that make antibodies, that grows in the bone marrow.

multiple sclerosisA long-term disease in which the immune system damages the protective covering of nerves in the brain and spinal cord.

mumpsA contagious disease caused by the mumps virus that mainly infects the salivary glands in front of the ears.

murmurAn extra whooshing or swishing sound heard with a stethoscope over the heart, made by turbulent blood flow.

muscularRelating to the muscles, or having well-developed muscles.

musculoskeletalHaving to do with the muscles, bones, joints, tendons and ligaments.

mutationA change in the genetic code (DNA) of a cell.

myastheniaWeakness of the muscles.

myasthenia gravisA long-term autoimmune disease in which antibodies block the signals passing from nerves to muscles.

myelinThe fatty covering wrapped around many nerve fibers that protects them and speeds up their signals.

myocardial infarctionDeath of part of the heart muscle because its blood supply is blocked; a heart attack.

myocardiumThe thick middle layer of the heart wall, made of heart muscle that contracts to pump blood.

myopathyA disease of the muscle tissue itself.

myopiaNearsightedness: close things are seen clearly but distant things look blurred.

NADNicotinamide adenine dinucleotide, a helper molecule in cell energy; in charting, often "no acute distress".

NADHThe form of NAD that carries electrons and energy from food to the cell's energy-making machinery.

nail bedThe skin underneath a fingernail or toenail.

narisA nostril, one of the two openings of the nose; the plural is nares.

nasalHaving to do with the nose.

nasal cannulaA thin plastic tube with two short prongs that sit in the nostrils to give oxygen.

nasal cavityThe space inside the nose, behind the nostrils, through which air passes on its way to the throat.

nasal septumThe wall of cartilage and bone that divides the inside of the nose into right and left sides.

nasogastric decompressionRemoving air and fluid from the stomach through a nasogastric tube attached to suction.

nasopharynxThe top part of the throat, behind the nose and above the soft palate.

natriureticMaking the kidneys remove more sodium in the urine.

natriuretic peptideA hormone released by stretched heart muscle that makes the kidneys remove sodium and water and relaxes the blood vessels.

nausea and vomitingFeeling sick to the stomach together with throwing up.

necrosisThe death of cells or tissue in a part of the body.

necrotizing enterocolitisA serious illness, mainly of premature babies, in which part of the bowel becomes inflamed and its tissue begins to die.

neonatalRelating to a newborn baby, in the first 28 days after birth.

neonatal abstinence syndromeWithdrawal in a newborn who was exposed before birth to opioids or other drugs the mother took.

neonateA newborn baby in the first 28 days of life.

nephritisInflammation of the kidneys.

nephrolithiasisThe forming of stones in the kidney.

nephrologistA physician who specializes in the kidneys and their diseases.

nephronThe tiny filtering unit of the kidney, where blood is filtered and urine is made.

nephrotic syndromeA kidney disorder in which damaged filters let large amounts of protein pass from the blood into the urine.

nerveA cord-like bundle of fibers that carries signals between the brain or spinal cord and other parts of the body.

nervous systemThe brain, spinal cord and nerves, which together carry messages that control the body.

neural tubeThe hollow structure in an early embryo that develops into the brain and spinal cord.

neuroblastomaA cancer that starts in immature nerve cells, most often in an adrenal gland, in young children.

neurologicalRelating to the nervous system: the brain, spinal cord and nerves.

neuromuscularHaving to do with both nerves and muscles, or with the place where a nerve meets a muscle.

neuronA nerve cell: a cell that carries electrical and chemical signals through the nervous system.

neuropathyDamage to or disease of one or more nerves, most often the nerves of the hands and feet.

neurotransmitterA chemical that a nerve cell releases to pass a signal to another nerve, muscle or gland cell.

neurovascularHaving to do with both the nerves and the blood vessels of a body part.

neurovascular checkAn assessment of blood flow, feeling and movement in a limb below an injury, cast, splint or surgery.