Pronunciation: (ō"lē-ō-rez'un), [key]
1. a mixture of an essential oil and a resin, found in nature.
2. Pharm.an oil holding resin in solution, extracted from a substance, as ginger, by means of alcohol, ether, or acetone.
Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease.