/ Dictionary / Index C cephalic index: Meaning and Definition of Find definitions for: cephal'ic in'dex Pronunciation: [key] the ratio of the greatest breadth of the head to its greatest length from front to back, multiplied by 100. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. cephalic cephalin Related Content Daily Word Quiz: tenacious Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language