Medical terms - Letter M (page 9) | MedicalVocabulary.org

Melanoma, superficial spreading

One of the four clinical types of malignant melanoma, the most common type in whites, typically presents as a raised, irregular, colored area that starts in a mole-like shape but spreads across the skin
Melanoma, uveal

See: Intraocular melanoma
Melanosis coli

Melanosis coli (Pseudomelanosis coli): A benign, reversible condition usually, but not always, associated with long-term use of anthranoid laxatives in which pigment deposition in the lamina propria of the large…
MELAS syndrome

MELAS syndrome: MELAS is the acronym for Mitochondrial Encephalopathy, Lactic Acidosis, and Stroke-like episodes. MELAS is a rare form of dementia. It is caused by mutations in the genetic material (DNA) in the…
Melasma

Pigmentation of the face, most commonly on the malar area (the upper cheek), bridge of nose, forehead, and upper lip, that occurs in half of women during pregnancy. Birth control pills can also cause melasma. However…
Melatonin

A hormone produced by the pineal gland, melatonin is intimately involved in regulating the sleeping and waking cycles, among other processes. Melatonin supplements are sometimes used by people who have chronic insomnia…
MELD

Acronym for Model End Stage Liver Disease. A disease severity scoring system for adults with liver disease, designed to improve the organ allocation in transplantation based on the severity of liver disease rather than…
Melena

Stools or vomit stained black by blood pigment or dark blood products.
Melioidosis

Melioidosis: An infectious illness, also called Whitmore's disease, that is most frequent in Southeast Asia and Northern Australia and is caused by a bacteria called 'Pseudomonas pseudomallei' found in soil, rice…
Melissophobia

Fear of bees. A phobia is an unreasonable sort of fear that can cause avoidance and panic. Phobias are a relatively common type of anxiety disorder. Phobias can be treated with cognitive behavioral therapy using…
Melittin

The principal toxic component in bee venom. Melittin is a relatively short peptide consisting of 26 amino acids. It is a powerful cell lytic agent and binds rapidly to red blood cells causing the release of hemoglobin…
Melomania

A singular passion for music that is beyond all reason. From the French melomanie, from the Latin melos, song + -mania, frenzy
Melorheostosis

A rare bone condition that usually begins in childhood characterized by thickening of the bones (sclerosis) of a limb. Pain is frequent in the involved limb. The affected bone can have the appearance of 'dripping candle…
Meltdown, genetic

A genomic crisis due to an extraordinarily high rate of mutation, a phenomenon known to occur in viruses and perhaps in other organisms. For example, the antiviral agent Ribavirin acts by inducing genomic meltdown. The…
Membrane

A very thin layer of tissue that covers a surface.
Membrane attack complex

Abbreviated MAC. An abnormal activation of the complement (protein) portion of the blood, forming a cascade reaction that brings blood proteins together, binds them to the cell wall, and then inserts them through the…
Membrane cofactor protein

See: MCP
Membrane metalloendopeptidase

See: Metallomembrane endopeptidase
Membrane, epiretinal

See: Macular pucker
Membrane, vaginal

A thin membrane which completely or partially occludes the vaginal opening. This fold of mucous membrane is usually present at birth at the orifice of the vagina. It is also called the hymen, a Greek word meaning 'skin'…
Membrane-associated neutral endopeptidase

Pertaining to a membrane. As in acute membranous gingivitis, membranous nephropathy, and pseudomembranous colitis.
Membranous

Pertaining to a membrane. As in acute membranous gingivitis, membranous nephropathy, and pseudomembranous colitis
Membranous gingivitis, acute

This is trench mouth, a progressive painful infection with ulceration, swelling and sloughing off of dead tissue from the mouth and throat due to the spread of infection from the gums. Certain germs (including fusiform…
Membranous glomerulonephritis

See: Membranous nephropathy
Membranous nephropathy

A frequent type of primary glomerular disease -- a disease affecting the glomerulus, the tiny ball-shaped structure in the kidney composed of capillary blood vessels that is actively involved in the filtration of the…
Membranous vitreous type Stickler syndrome

Yndrome, type I. See: Stickler syndrome
Memory

1. The ability to recover information about past events or knowledge. 2. The process of recovering information about past events or knowledge. 3. Cognitive reconstruction. The brain engages in a remarkable reshuffling…
Memory B cells

Secondary immune-system components that have an affinity for a particular antigen. Like other B cells, memory B cells originate from lymphocytes that develop and are activated in the bone marrow. They become…
Memory span

The number of items, usually words or numbers, that a person can retain and recall. Memory span is a test of working memory (short-term memory). In a typical test of memory span, an examiner reads a list of random…
Memory, anterograde

See: Anterograde memory
Memory, explicit

See: Explicit memory
Memory, implicit

See: Implicit memory
Memory, long-term

A system for permanently storing, managing, and retrieving information for later use. Items of information stored as long-term memory may be available for a lifetime. Long-term memory is in contrast to short-term memory…
Memory, recent

Short-term memory. Also called working memory. Recent memory is a system for temporarily storing and managing the information required to carry out complex cognitive tasks such as learning, reasoning, and comprehension…
Memory, short-term

A system for temporarily storing and managing information required to carry out complex cognitive tasks such as learning, reasoning, and comprehension. Short-term memory is involved in the selection, initiation, and…
Memory, working

Short-term (recent) memory. Working memory is a system for temporarily storing and managing the information required to carry out complex cognitive tasks such as learning, reasoning, and comprehension. Working memory is…
Menangle virus

A virus that causes a disease first found in a piggery near Sydney, Australia in 1997. The virus was highly contagious, moving between pigs in different pens and sheds. It caused numerous deformed and stillborn piglets…
Menarche

The time in a girl's life that menstruation first begins. During the menarche period, menstruation may be irregular and unpredictable. Mood, weight, activity level, and growth rate may fluctuate with the hormone levels…
Mendel, Gregor

The great Moravian/Bohemian biologist (1822-84) who set forth the basic laws that constitute the foundation of classical genetics. Mendelian inheritance is the manner in which genes and traits are passed from parents to…
Mendelian

Referring to the great Moravian/Bohemian biologist Gregor Mendel (1822-84) who set forth the basic laws that constitute the foundation of classical genetics. Mendelian inheritance is the manner in which genes and traits…
Mendelian inheritance

The manner in which genes and traits are passed from parents to their children. The four modes of Mendelian inheritance are autosomal dominant, autosomal recessive, X-linked dominant and X-linked recessive. The term…
Mendelism

The principles of genetics, specifically of single-gene traits, based on the work of Gregor Mendel (1822-84), a Moravian monk and biologist who established the laws that are the foundation of classical genetics. Mendel…
Menetrier disease

See: Giant hypertrophic gastritis
Menetrier disease

See: Giant hypertrophic gastritis
Menetrier's disease

See: Giant hypertrophic gastritis
Menetrier's disease

See: Giant hypertrophic gastritis
Meniere disease

Meniere disease: A condition with recurrent vertigo accompanied by ringing in the ears (tinnitus) and deafness. Symptoms include vertigo, dizziness, nausea, vomiting, loss of hearing (in the affected ear), and abnormal…
Meninges

The three membranes that cover the brain and spinal cord (singular: meninx). The outside meninx is called the dura mater, and is the most resilient of the three. The center layer is the arachnoid membrane and the thin…
Meningioma

A common type of slow growing, usually benign brain tumor that arises from the dura, one of the meninges, the membranes covering the brain and spinal cord. A meningioma may occur wherever there is dura but the most…
Meningitis

Inflammation of the meninges, usually due to a bacterial infection but sometimes from viral, protozoan, or other causes (in some cases the cause cannot be determined). The onset is usually rapid (acute), and if…