/ Dictionary / Index S sulfinyl: Meaning and Definition of Find definitions for: sul•fi•nyl Pronunciation: (sul'fu-nil), [key] — adj. Chem. containing the sulfinyl group; thionyl. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. sulfinpyrazone sulfinyl group Related Content Daily Word Quiz: meddlesome Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language