/ Dictionary / Index T thalamium: Meaning and Definition of Find definitions for: tha•la•mi•um Pronunciation: (thu-lā'mē-um), [key] — pl. -mi•a thalamus (def. 3). Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. thalamencephalon thalamus Related Content Daily Word Quiz: wizened Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language