/ Dictionary / Index S sextodecimo: Meaning and Definition of Find definitions for: sex•to•dec•i•mo Pronunciation: (sek"stō-des'u-mō"), [key] — n., pl. adj. -mos, —n. sixteenmo (def. 1). —adj. sixteenmo (def. 3). Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. sextillion sexton Related Content Daily Word Quiz: paradox Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language