柯林斯詞典atomic mass 1. N the mass of an isotope of an element in atomic mass units 原子質(zhì)量[chem] 返回 atomic mass劍橋詞典the mass of a specific isotope of a particular chemical element , usually expressed in atomic mass units 原子質(zhì)量（某化學(xué)元素同位素的質(zhì)量，通常以原子質(zhì)量單位的形式表達(dá)） 比較relative atomic mass 返回 atomic mass