/ Dictionary / Index T three-phase: Meaning and Definition of Find definitions for: three-phase Pronunciation: (thrē'fāz"), [key] — adj. Elect. of or pertaining to a circuit, system, or device that is energized by three electromotive forces that differ in phase by one third of a cycle or 120°. having three phases. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. threepenny three-piece Related Content Daily Word Quiz: mamba Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language