/ Dictionary / Index T Tombaugh: Meaning and Definition of Find definitions for: Tom•baugh Pronunciation: (tom'bô), [key] — n. born 1906, U.S. astronomer: discovered the planet Pluto 1930. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. See also: tombaugh (Thesaurus) Tombalbaye tombé Related Content Daily Word Quiz: deleterious Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language