Gila monster \Gi"la mon"ster\ (Zo["o]l.) A large tuberculated lizard ({Heloderma suspectum}) native of the dry plains of Arizona, New Mexico, etc. It is the only lizard known to have venomous teeth.
Heloderma suspectum n : large orange and black lizard of southwestern United States; not dangerous unless molested [syn: {Gila monster}]