/ Dictionary / Index C crucial: Meaning and Definition of Find definitions for: cru•cial Pronunciation: (kr'shul), [key] — adj. involving an extremely important decision or result; decisive; critical: a crucial experiment. severe; trying. of the form of a cross; cross-shaped. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. See also: crucial (Thesaurus) cruces crucian carp Related Content Daily Word Quiz: eccentric Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language