mass (redirected from Mass (physics))

mass (mas)

1. a lump or collection of cohering particles.

2. a cohesive mixture to be made into pills.

3. the characteristic of matter that gives it inertia. Symbol m.

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atomic mass  atomic weight; used particularly when describing a single isotope of a nuclide.

inner cell mass  embryoblast.

lean body mass  that part of the body including all its components except neutral storage lipid; in essence, the fat-free mass of the body.

molar mass  (M ) the mass of a molecule in grams (or kilograms) per mole.

molecular mass  the mass of a molecule in daltons, derived by addition of the component atomic masses. Its dimensionless equivalent is molecular weight.

relative molecular mass  technically preferable term for molecular weight. Symbol M r.

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mass (ms)

n.

1. A unified body of matter with no specific shape.

2. A grouping of individual parts or elements that compose a unified body of unspecified size or quantity.

3. The physical volume or bulk of a solid body.

4. Abbr. m The measure of the quantity of matter that a body or an object contains. The mass of the body is not dependent on gravity and therefore is different from but proportional to its weight.

5. A thick, pasty pharmacological mixture containing drugs from which pills are formed.

6. One of the seven fundamental SI units, the kilogram.

7. See massa.

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mass

1. a lump or collection of cohering particles.

2. that characteristic of matter which gives it inertia.

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mass-action ratios

the ratio of substrate to product, where the predominance of one, usually the substrate, over the other thermodynamically favors a particular direction for a reaction.

inner cell mass

an internal cluster of cells at the embryonic pole of the blastocyst which develops into the body of the embryo.

lean body mass

that part of the body including all its components except neutral storage lipid; in essence, the fat-free mass of the body.

mass medication

(or immunization, or treatment, or prophylaxis, or testing, or screening) application of the procedure to all of the animals in the population, which may be as small as a herd or as large as a national herd. This sort of strategy has been used extensively and for many years in the control of diseases of animals, and has been the principal reason for the dramatic virtual eradication of the major plagues in many countries. The unintelligent extension of the strategy to the control of wastage caused by endemic disease has contributed most to the problem of residues of antibacterial drugs in the human food chain. See also mass medication.

mass number

the number used to express the mass of a nucleus, being the total number of nucleons, protons and neutrons in the nucleus of an atom or nuclide; symbol A.

mass reflex

reflex actions by all the body parts controlled by the part of the spinal cord which has been injured.

thalamic intermediate mass

see interthalamic adhesion.