Medical terms - Letter M (page 4) | MedicalVocabulary.org

Mapping

Charting the location of genes on chromosomes.
Mapping, gene

The process of determining the relative positions of genes on a chromosome (or another piece of DNA) and the distances between the genes in linkage units or in physical units
Marasmus

Wasting away, as occurs with children who have kwashiorkor. Also called cachexia, is usually a result of protein and calorie deficiency.
Marburg disease

The virus that causes Marburg hemorrhagic fever, a disease which affects both humans and non-human primates. Caused by a genetically unique zoonotic (that is, animal-borne) RNA virus of the filovirus family, its…
Marburg virus

An inherited disorder of connective tissue characterized by abnormalities of the eyes, skeleton, and cardiovascular system. Myopia (nearsightedness) is the most common eye feature. Displacement of the lens from the…
Marfan syndrome

Marfan syndrome: An inherited disorder of connective tissue characterized by abnormalities of the eyes, skeleton, and cardiovascular system. Myopia (nearsightedness) is the most common eye feature. Displacement of the…
Margaret Mead

See: Mead, Margaret
Marie-Strumpell disease

A synonym for ankylosing spondylitis. Named for the French neurologist Pierre Marie (1853-1940) and the German neurologist whose full name was Ernst Adolf Gustav Gottfried von Str¨mpell (1853-1925). See: Ankylosing…
Marijuana

Marijuana: A very common street and recreational drug that comes from the marijuana plant. The plant that produces marijuana, as is well known, is the hemp plant cannabis sativa. The pharmacologically active ingredient…
Marinesco-Sjogren syndrome

Syndrome: A genetic disorder characterized by very small stature, cerebellar ataxia (wobbliness), cataracts, muscle weakness, hypogonadism (low gonadal function), and developmental and mental retardation. The disease is…
Mark of Cain

The mark that God set upon Cain, the eldest son of Adam. According to the Book of Genesis in the Bible, God rejected Cain's grain offering while accepting the animal offering of his brother Abel. Out of jealousy, Cain…
Marker

A piece of DNA that lies on a chromosome so close to a gene that the marker and the gene are inherited together. A marker is thus an identifiable heritable spot on a chromosome. A marker can be an expressed region of…
Marker chromosome

An abnormal chromosome that is distinctive in appearance but not fully identified. A marker chromosome is not a 'marker' of a specific disease. It is a marker chromosome merely in the sense that it can be distinguished…
Marker gene

A detectable genetic trait or segment of DNA that can be identified and tracked. A marker gene can serve as a flag for another gene, sometimes called the target gene. A marker gene must be on the same chromosome as the…
Marker, blood

A sign of a disease or condition that can be isolated from a blood sample. For example, the monoclonal antibody D8/17 is a diagnostic sign of Pediatric Autoimmune Disorders associated with Strep
Marker, tumor

Tumor markers are substances that can be detected in higher-than-normal amounts in the blood, urine, or body tissues of some patients with certain types of cancer. A tumor marker may be made by a tumor itself or by the…
Marmoreal

Resembling marble. For example, the bone in osteoporosis appears marmoreal. From the Latin noun 'marmor' meaning 'marble.
Maroteaux-Lamy syndrome

A form of mucopolysaccharidosis with the clinical onset before age 3 that is characterized by an inability to metabolize dermatan sulfate. This leads to abnormal accumulation of dermatan sulfate, resulting in mild to…
Marriage, cousin

A form of consanguinity. Everyone carries recessive alleles, genes that are generally innocuous in the heterozygous state but that in the company of another gene of the same type are capable of causing disease. We are…
Marrow

The bone marrow
Marsh fever

See malaria
Marshall W. Nirenberg

A disorder characterized by advanced bone age at birth, broad forehead, prominent eyes, and small chin. There is difficulty feeding, failure to thrive, retarded psychomotor development, and predisposition to respiratory…
Marshall-Smith syndrome

A disorder characterized by advanced bone age at birth, broad forehead, prominent eyes, and small chin. There is difficulty feeding, failure to thrive, retarded psychomotor development, and predisposition to respiratory…
Martin Rodbell

See: Rodbell, Martin
Martinus W. Beijerinck

See: Beijerinck, Martinus W.
Martorell syndrome

Named after Fernando Martorell Otzet, Spanish cardiologist (1906-1984). In 1944 Martorell provided an excellent description of a syndrome also known today as Takayasu disease. See: Takayasu disease
Marx

See: Marx, Gertie F.
Marx, Gertie F.

Distinguished German-born American physician known as the 'mother of obstetric anesthesia.' She almost singlehandedly developed obstetric anesthesiology as a specialty. She advanced the use of epidural injections to…
MASA syndrome

MASA stands for mental retardation, aphasia, shuffling gait, and adducted thumbs. Features of the syndrome include: > >neurologically: mental retardation and aphasia (lack of speech); >limbs: adducted (clasped) thumbs…
Mask of pregnancy

Muddy-brown pigmentation on the cheeks or elsewhere on the face that develops in about half of all women during pregnancy. Some women also develop it outside pregnancy, as do some women on hormone therapy. The…
Mask, oxygen

A mask that covers the mouth and nose, and is hooked up to an oxygen tank. It delivers oxygen directly to the patient. Oxygen can also be delivered directly through a nasal catheter, a tube that divides into two smaller…
Masklike face

An expressionless face with little or no sense of animation, a face more like a mask than a real face. A masklike face is seen in a number of disorders including Parkinson's disease and myotonic dystrophy. Also called…
Masochism

Pleasure from one's own pain. Masochism is considered a sexual disorder, or paraphilia. Named after the 19th-century Austrian writer Leopold von Sacher-Masoch (masoch-ism).
Mass spectrometry

An instrument used to identify chemicals in a substance by their mass and charge. Mass spectrometers are instruments that essentially weigh molecules. A mass spectrometer also can measure how much of a compound is…
MASS syndrome

A heritable disorder of connective tissue characterized by involvement of the mitral valve, aorta, skeleton, and skin. Hence, the acronym MASS (Mitral valve, Aorta, Skeleton, Skin). The MASS syndrome is due to a…
Massage

The manipulation of muscle and connective tissue to enhance the function of those tissues and promote relaxation and well-being. Therapeutic massage can ease tension and reduce pain. Massage can be a part of physical…
Massage therapist

A person who practices therapeutic massage. In many US states, massage therapists can be licensed after completing a specified training program. Licensed therapists may practice independently or in a medical setting
Masseter

The muscle that raises the lower jaw.
Mast cell

A connective tissue cell whose normal function is unknown but which is frequently injured in allergic reactions, releasing chemicals including histamine that are very irritating and cause itching, swelling, and fluid…
Mast cell tumor

A mastocytoma
Mast syndrome

An autosomal recessive form of hereditary spastic paraplegia with dementia first described in the Old Order Amish. The disease usually surfaces in early adulthood and is slowly progressive. The Mast syndrome gene is in…
Mastalgia

Pain in the breast or mammary gland. From the Greek masto-, breast + algos, pain
Mastectomy

A general term for removal of the breast, usually to remove cancerous tissue. The operation can be done in a hospital or in an outpatient clinic, depending on how extensive it needs to be. It takes from two to three…
Mastectomy, double

Removal of both breasts
Mastectomy, modified radical

Removal of the breast tissue and the axillary lymph nodes, which are under the arms
Mastectomy, preventative

Removal of one or both breasts without the current presence of cancer. This surgery is sometimes chosen as a preventative measure by women who have a strong history of familial breast cancer
Mastectomy, prophylactic

Removal of one or both breasts without the current presence of cancer. This surgery is sometimes chosen as a preventative measure by women who have a strong history of familial breast cancer. Also called a preventative…
Mastectomy, radical

Removal of all breast tissue, from just under the collar bone to the abdomen, including the chest wall muscles. The axillary lymph nodes are also removed. This operation is rarely used anymore, having first been…
Mastectomy, simple

Removal of one or both breasts, but not the lymph nodes
Mastectomy, subcutaneous

Removal of breast tissue using a minimal incision. This type of mastectomy may be used to remove small areas of suspicious or cancerous tissue, but can also be a cosmetic surgery procedure. For example, subcutaneous…