Pronunciation: (pen'tān), [key]
—n. Chem., Pharm.
1. a hydrocarbon of the methane series, existing in three liquid isomeric forms.
2. Also called normal pentane. the most important isomer of pentane, a colorless, flammable, water-insoluble, very volatile liquid, C5H12, obtained from petroleum by distillation: used chiefly as a solvent and in medicine as an anesthetic.
Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease.