Pronunciation: (ka-stēl'), [key]
1. Spanish, Cas•ti•lla Pronunciation: (käs-tē'lyä, -yä). [key]a former kingdom comprising most of Spain.
2. Also called Castile' soap'. a variety of mild soap, made from olive oil and sodium hydroxide.
3. any hard soap made from fats and oils, often partly from olive oil.
Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease.