/ Dictionary / Index S sigmate: Meaning and Definition of Find definitions for: sig•mate Pronunciation: (sig'mit, -māt), [key] — adj. having the form of the Greek sigma or the letter S. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. sigma particle sigmatism Related Content Daily Word Quiz: cetacean Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language