/ Dictionary / Index Y YAG: Meaning and Definition of Find definitions for: YAG Pronunciation: (yag), [key] — n. a synthetic yttrium aluminum garnet, used for infrared lasers and as a gemstone. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. Yafo yage Related Content Daily Word Quiz: profiterole Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language