/ Dictionary / Index I illegitimacy: Meaning and Definition of Find definitions for: il•le•git•i•ma•cy Pronunciation: (il"i-jit'u-mu-sē), [key] — pl. -cies. the state or quality of being illegitimate. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. See also: illegitimacy (Thesaurus) illegit illegitimate Related Content Daily Word Quiz: spectral Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language