| atomic mass | |
| —n | |
| 1. | the mass of an isotope of an element in atomic mass units |
| 2. | short for relative atomic mass See atomic weight |
| the offspring of a zebra and a donkey. |
| a chattering or flighty, light-headed person. |
atomic mass n.
The mass of an atom, usually expressed in atomic mass units.
| atomic mass
The mass of a given atom or molecule, expressed in atomic mass units. Compare atomic weight. See also mass number. |
atomic mass
the quantity of matter contained in an atom of an element. It is expressed as a multiple of one-twelfth the mass of the carbon-12 atom, 1.992646481023gram, which is assigned an atomic mass of 12 units. In this scale 1 atomic mass unit (amu) corresponds to 1.660538731024gram.
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