atomic number

noun

Definition of atomic number

:an experimentally determined number characteristic of a chemical element that represents the number of protons in the nucleus which in a neutral atom equals the number of electrons outside the nucleus and that determines the place of the element in the periodic table — see Chemical Elements Table

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First Known Use of atomic number

1913


Medical Dictionary

atomic number

noun atomic num·ber \ -ˈnəm-bər \

medical Definition of atomic number

:an experimentally determined number characteristic of a chemical element that represents the number of protons in the nucleus which in a neutral atom equals the number of electrons outside the nucleus and that determines the place of the element in the periodic table — see Chemical Elements Table

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