The Collaborative International Dictionary of English v.0.48:
Helodermatidae \Helodermatidae\ prop. n. A natural family of lizards, including the only known venomous lizards. Syn: family Helodermatidae. [WordNet 1.5]WordNet (r) 3.0 (2006):
Helodermatidae n 1: only known venomous lizards [syn: Helodermatidae, family Helodermatidae]