/ Dictionary / Index M mater: Meaning and Definition of Find definitions for: ma•ter Pronunciation: (mā'tur), [key] — pl. -ters, -tres mother. the backing holding the movable parts of an astrolabe. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. See also: mater (Thesaurus) matelote mater dolorosa* Related Content Daily Word Quiz: clairvoyant Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language