/ Dictionary / Index D duodecillion: Meaning and Definition of Find definitions for: du•o•de•cil•lion Pronunciation: (d"ō-di-sil'yun, dy"-), [key] — n., pl. adj. -lions, -lion, —n. a cardinal number represented in the U.S. by 1 followed by 39 zeros, and in Great Britain by 1 followed by 72 zeros. —adj. amounting to one duodecillion in number. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. duodecastyle duodecimal Related Content Daily Word Quiz: pristine Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language