Webster’s Revised Unabridged Dictionary · 1913
Valylene
Val′yl·ene (văl′ĭl·en), n. [Valerian + -yl.] (Chem.) A volatile liquid hydrocarbon, C5H6, related to ethylene and acetylene, but possessing the property of unsaturation in the third degree. It is the only known member of a distinct series of compounds. It has a garlic odor.