/ Dictionary / Index T thinking cap: Meaning and Definition of Find definitions for: think'ing cap" Pronunciation: [key] a state of mind marked by reflection or concentration: If we put on our thinking caps, we may come up with the answer. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. thinking think piece Related Content Daily Word Quiz: knead Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language