atomic mass (redirected from Atomic masses)

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.

---

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.

---

atomic mass

n.

The mass of an atom, usually expressed in atomic mass units.

---

atomic mass (A),

the average mass, relative to an atom of carbon, of an atom of an element based on the natural isotopic mix of that element. Also called atomic weight. See also atomic mass unit.