atomic number

noun

Definition of atomic number

  1. :  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 element table

First Known Use of atomic number

1913


Medical Dictionary

atomic number

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noun atomic num·ber \-ˈnəm-bər\

Medical Definition of atomic number

  1. :  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 element table


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