[noo-klahyd, nyoo-]
noun Physics.
  1. an atomic species in which the atoms all have the same atomic number and mass number.
  2. an individual atom in such a species.

Origin of nuclide

1945–50; nucl(eo)- + -ide < Greek eîdos shape Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018

British Dictionary definitions for nuclide


  1. a species of atom characterized by its atomic number and its mass numberSee also isotope

Word Origin for nuclide

C20: from nucleo- + -ide, from Greek eidos shape
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Word Origin and History for nuclide

1947, from nucleus + -ide.

Online Etymology Dictionary, © 2010 Douglas Harper

nuclide in Medicine


  1. A type of atom specified by its atomic number, atomic mass, and energy state, such as carbon 14.
Related formsnu•clidic (nōō-klĭdĭk) adj.
The American Heritage® Stedman's Medical Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Company. Published by Houghton Mifflin Company.

nuclide in Science


  1. An atomic nucleus identified by its atomic element and its mass number. For example, a carbon-14 nuclide is the nucleus of a carbon atom, which has six protons, with mass number 14 (thus having eight neutrons). See also isotope.
The American Heritage® Science Dictionary Copyright © 2011. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.