/ Dictionary / Index U ultrametamorphism: Meaning and Definition of Find definitions for: ul•tra•met•a•mor•phism Pronunciation: (ul"tru-met"u-môr'fiz-um), [key] — n. Geol. metamorphism during which the temperature of a rock exceeds its melting point. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. ultramarine ultramicrobalance Related Content Daily Word Quiz: opulent Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language