/ Dictionary / Index A acid dust: Meaning and Definition of Find definitions for: ac'id dust' Pronunciation: [key] air-polluting particles of dust, usually wind-borne, having high concentrations of acid. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. acid drop acid dye Related Content Daily Word Quiz: resilient Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language