/ Dictionary / Index I inefficient: Meaning and Definition of Find definitions for: in•ef•fi•cient Pronunciation: (in"i-fish'unt), [key] — adj. not efficient; unable to effect or achieve the desired result with reasonable economy of means. lacking in ability, incompetent. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. See also: inefficient (Thesaurus) inefficiency inegalitarian 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