/ Dictionary / Index T tonsil: Meaning and Definition of Find definitions for: ton•sil Pronunciation: (ton'sul), [key] — n. Anat. a prominent oval mass of lymphoid tissue on each side of the throat. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. See also: tonsil (Thesaurus) tonoplast tonsillectomy Related Content Daily Word Quiz: frugal Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language