/ Dictionary / Index W whoso: Meaning and Definition of Find definitions for: who•so Pronunciation: (h'sō), [key] — whom•so. whosoever; whoever. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. whosis whosoever Related Content Daily Word Quiz: soporific Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language