Dictionary
alu'minum ammo'nium sul'fate
Chem.
a crystalline solid, AlNH
4(SO
4)
2·12H
2O, used chiefly as a size in the manufacture of paper; alum. Also called
ammonium alum, ammonia alum. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease.