/ Dictionary / Index E exon: Meaning and Definition of Find definitions for: ex•on Pronunciation: (ek'son), [key] — n. (in Britain) one of four yeomen of the guard who act as commanding officers in the absence of higher authority. Also called ex•on Pronunciation: (ek'son), [key] — n. Genetics. any portion of an interrupted gene that is represented in the RNA product and is translated into protein. Cf. intron. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. See also: exon (Thesaurus) exogenous exonarthex Related Content Daily Word Quiz: gregarious Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language