/ Dictionary / Index U unthinking: Meaning and Definition of Find definitions for: un•think•ing Pronunciation: (un-thing'king), [key] — adj. thoughtless; heedless; inconsiderate: an unthinking, tactless person. indicating lack of thought or reflection: a dull, unthinking expression on his face. not endowed with the faculty of thought: unthinking matter. not exercising thought; not given to reflection: This book will not profit an unthinking person. not thinking; unmindful: chores done in an unthinking manner. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. See also: unthinking (Thesaurus) unthinkable unthought Related Content Daily Word Quiz: spectral Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language