/ Dictionary / Index A aluminum sulfate: Meaning and Definition of Find definitions for: alu'minum sul'fate Pronunciation: [key] — Chem. Chem. a white, crystalline, water-soluble solid, Al(SO), used chiefly as a water-purifying agent, as a mordant, and as a size in the manufacture of paper. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. aluminum soap alumna Related Content Daily Word Quiz: labyrinth Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language