/ Dictionary / Index N nuclide: Meaning and Definition of Find definitions for: nu•clide Pronunciation: (n'klīd, ny'-), [key] — n. Physics. an atomic species in which the atoms all have the same atomic number and mass number. an individual atom in such a species. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. nucleus counter Nudd Related Content Daily Word Quiz: pristine Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language