| MACROPHAGE: |
Large cells found throughout the body, particularly in the spleen, that have the ability to ingest other substances such as "old" red blood cells; also important in the immune response. |
| MACROSOMIA: |
Larger-than-normal birth weight (usually more than 9 ¾ pounds, or 4,500 grams). |
| MAGNETIC RESONANCE IMAGING (M.R.I.): |
A noninvasive diagnostic procedure using radio waves and magnetic fields to provide a highly detailed map of an interior structure of the body, such as the brain. MRI depicts detailed internal anatomy by exploiting the interaction of the magnetic properties of atoms with an external magnetic field. |
| MALABSORPTION: |
Defective absorption of fluids. |
| MALIGNANT: |
Describes any disease which progresses rapidly, spreading to other parts of the body and eventually leading to death. |
| MALLEUS: |
The outermost of three tiny bones, connecting the eardrum to the vibration-sensitive structures of the inner ear and thereby amplifying and transmitting sound waves. |
| MALOCCLUSION: |
Refers to an abnormal fit of the upper and lower dental structures. |
| MANDIBLE: |
The mandible is the the bone of the lower jaw. The joint where the mandible meets the upper jaw at the temporal bone is called the temporomandibular joint. |
| MATROCLINAL: |
Traits transmitted from the mother. |
| MAXILLA: |
Upper jawbone. |
| MEATUS: |
The outer opening of a passageway of the body. |
| MECONIUM: |
A newborn's first bowel discharge, which is usually black or green. |
| MECONIUM ASPIRATION: |
A situation where meconium (greenish fecal matter, the first bowel movement of a fetus) filled amniotic fluid is breathed into the infant's lungs during the birth process. There may or may not be subsequent anoxia resulting in brain damage. Meconium aspiration is rare in babies born at less than 34 weeks gestation, and may be as high as 40 percent in post term babies. |
| MEDIA: |
The middle, muscular layer in the wall of an artery. |
| MEDIAL: |
The side of the body or body part that is nearer to the middle or center (median) of the body. For example, when referring to the knee, medial would mean the side of the knee that is closest to the other knee The opposite of medial is lateral. |
| MEDIAL COMPARTMENT: |
The inner of the two joint areas between the thigh-bone (femur) and shin-bone (tibia). |
| MEDIAL MENISCUS: |
The cartilage lining the inner upper end of the shin-bone (tibia). |
| MEDIASTINUM: |
The area that separates the lungs from each other. It contains the heart and its large veins and arteries, the trachea (wind-pipe), the esophagus, the thymus gland, and lymph nodes. |
| MEDULLA: |
The central part of the structure of an organ. |
| MEDULLA OBLONGATA: |
The tapering caudal position of the hind brain. |
| MEGACEPHALY: |
Unusually large head. |
| MEIOSIS: |
Constriction of the pupil of the eye. |
| MELANIN: |
Dark brown/black shapeless pigments found in melanotic tumours, the hair, skin, part of the brain and the choroid coat of the eye. |
| MELANOCYTES: |
Cells in the skin that produce and contain the pigment called melanin. |
| MEMBRANE: |
Thin elastic tissue which covers the surface of certain organs and lines the cavities of the body. |
| MENINGES: |
The three membranes that cover the spinal cord and brain. |
| MENINGOCELE: |
Hernia of the meninges of the spinal cord or brain. |
| MENINGOMYOCELE: |
Hernia of some portion of the spinal cord and its meninges. |
| MENISCUS: |
A crescentic cartilage (gristle) lying on either side (medial and lateral) of the upper end of the tibia (shin bone), cushioning the joint with the femur (thigh bone). |
| MENTAL: |
Relating to the mind. |
| MESENTERY: |
Fold in the abdominal lining that connects the intestine to the back of the abdominal wall; contains the arteries and veins that supply the intestines. |
| MESOCOLON: |
The fold of peritoneum, or mesentery, attached to the colon, that holds the lower colon the back abdominal wall. |
| METABOLIC DISORDER: |
1. A condition or disease related to dysfunction in the chemical processes and activities of the body.
2. Defects in the body's ability to process substances and nutrients normally. Lack of treatment for people with metabolic errors will result in mental retardation and in some cases death. In many of these conditions the primary treatment is diet. These conditions are rare and should be treated at centers that specialize in these disorders. Also referred to as "inborn errors". |
| METABOLISM: |
Physical and chemical processes by which food is transformed into energy and tissues are broken down into waste products. It is a two-part process: One part is called catabolism -- when the body uses food for energy. The other is called anabolism -- when the body uses food to build or mend cells. |
| METATARSALS: |
Bones just behind the toes. |
| MICROGNATHIA: |
Abnormally small (lower) jaw. |
| MICROPTHALMOS: |
An abnormally small eyeball. |
| MIDBRAIN: |
The uppermost of the three segments of the brainstem, primarily serving as an intermediary between the rest of the brain and the spinal cord. |
| MIDDLE CEREBRAL ARTERY: |
One of three sets of paired arteries supplying oxygen-rich blood to the cerebral hemispheres and originating from the Circle Of Willis near the termination of the internal carotid artery. |
| MIDLINE: |
The middle of the body; head in midline refers to the head in alignment with the spine. |
| MIDTRIMESTER: |
The middle three months of pregnancy. |
| MITRAL REGURGITATION: |
Backflow of oxygen-rich blood from the larger and more muscular left ventricle back into the smaller left atrium of the heart (and thus to the lungs) because of malfunctioning of the mitral valve due to pathological distortion of one or more of its components. |
| MITRAL VALVE: |
Heart valve that allows blood to move from the left atrium into the left ventricle and prevents the reverse flow. |
| MITRAL VALVE PROLAPSE: |
Bulging of the leaflets of the mitral valve into the left atrium during the heart's contraction. |
| MOLARS: |
The grinding or chewing teeth, located at the back of both jaws. |
| MONO-: |
Prefix denoting single. |
| MONOCYTES: |
Largest single cells with a nucleus seen in normal blood. |
| MONOPLEGIA: |
Paralysis that involves one limb. |
| MORBIDITY RATE: |
The sickness rate; the number of people who are sick or have a disease compared with the number who are well. |
| MORTALITY RATE: |
The death rate; the number of people who die of a certain disease compared with the total number of people. Mortality is most often stated as deaths per 1,000, per 10,000, or per 100,000 persons. |
| MOTILITY: |
Ability to move. |
| MOTOR: |
Relating to movement. |
| MOTOR DEVELOPMENT: |
The increasing ability to use muscles. |
| MULTIPARA: |
A woman who has given birth to more than one baby. |
| MULTIPLE GESTATION: |
More than one fetus developing in the uterus. |
| MULTIPLE POLYPOSIS: |
A disease characterized by numerous polyps in the colon and rectum. May also be referred to as familial polyposis. |
| MURMUR: |
Sounds made by turbulent blood moving through the chambers and valves of the heart or through the blood vessels near the heart, may signify a structural defect in the heart or valves. |
| MUSCLE WASTING: |
Loss of muscle bulk because of disuse or pathological process. |
| MUSCLES: |
Bundles of specialized cells that can contract and relax to create movement for the body itself and the organs within it. |
| MUSCULOSKELETAL: |
Includes the bones, joints, and surrounding soft tissue such as the skin, muscles, ligaments, and joint capsules. |
| MUTATION: |
A change in the genetic material that occurs by chance. |
| MY-: |
Relating to muscle. |
| MYELIN: |
Fatty sheath which encloses certain nerve fibres in the central nervous system. |
| MYELOMENINGOCELE: |
Spina Bifida in association with the protrusion of the spinal cord and its membranes. |
| MYOCARDIUM: |
The heart muscle. |
| MYOCLONIC: |
A type of muscle contraction. |
| MYOPATHY: |
Weakening or wasting occurring in muscles. |
| MYOTONIA: |
Delay in the relaxation of a muscle after voluntary contraction. |
