/ Dictionary / Index W whatsis: Meaning and Definition of Find definitions for: whats•is Pronunciation: (hwuts'is, hwots'-, wuts'-, wots'-), [key] — n. Informal. a thing or object whose name one does not know or cannot recall. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. See also: whatsis (Thesaurus) what's whatsit Related Content Daily Word Quiz: stringent Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language