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English definition of “atomic number”

atomic number

noun [C]     specialized
the number of protons found in the nucleus of an atom of a particular chemical, used as a way of listing the chemical elements in order in the periodic tableAtoms, molecules and sub-atomic particlesPhysical properties of solids, liquids and gases
(Definition of atomic number noun from the Cambridge Advanced Learner's Dictionary & Thesaurus © Cambridge University Press)
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