atomic massatomic mass
the mass of a given atom, usually expressed in atomic mass units: it is the atomic weight multiplied by the atomic mass unit
The mass of an atom, usually expressed in atomic mass units.
(plural atomic masses)
- The mass of an atom.
- (proscribed) atomic weight; the average mass of atoms of an element.
Atomic mass may be measured in absolute terms, or, commonly, as a sum of the number of protons and neutrons in the nucleus.