Pronunciation: (lē'thul), [key]
1. of, pertaining to, or causing death; deadly; fatal: a lethal weapon; a lethal dose.
2. made to cause death: a lethal chamber; a lethal attack.
3. causing great harm or destruction: The disclosures were lethal to his candidacy.
Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease.