pit viper
noun
1- a venomous snake of a group distinguished by visible sensory pits on the head which can detect prey by heat. They are found in both America and Asia.蝮亚科毒蛇。
1.1
- Subfamily Crotalinae, family Viperidae: numerous genera and species, including the rattlesnakes.蝮亚科, 蝰科：众多属及众多种, 包括响尾蛇。