Definition that contains atomic mass
- heavy (physics, chemistry) being or containing an isotope with greater than average atomic mass or weight
- atomic mass (chemistry) the mass of an atom of a chemical element expressed in atomic mass units
- relative atomic mass (chemistry) the mass of an atom of a chemical element expressed in atomic mass units
- atomic weight (chemistry) the mass of an atom of a chemical element expressed in atomic mass units
- relative molecular mass (chemistry) the sum of the relative atomic masses of the constituent atoms of a molecule
- molecular weight (chemistry) the sum of the relative atomic masses of the constituent atoms of a molecule