/ Dictionary / Index T thin register: Meaning and Definition of Find definitions for: thin' reg"ister Pronunciation: [key] — Music. Music. See Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. thinnish thin-skinned Related Content Daily Word Quiz: loathe Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language