/ Dictionary / Index S sulfur butterfly: Meaning and Definition of Find definitions for: sul'fur but'terfly Pronunciation: [key] any of various yellow or orange butterflies of the family Pieridae. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. sulfur-bottom sulfur dioxide Related Content Daily Word Quiz: frugal Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language