/ Dictionary / Index G gallium arsenide: Meaning and Definition of Find definitions for: gal'lium ar'senide Pronunciation: [key] — Chem. Chem. a crystalline and highly toxic semiconductor, GaAs, used in light-emitting diodes, lasers, and electronic devices. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. gallium gallivant Related Content Daily Word Quiz: lyceum Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language