n.large extremely venomous pit viper of Central America and South America
同义词：Bothrops atrops
英汉双解大词典
fer-de-lance/ˌfɛədəˈlɑːns/
1.
N（名词）
a large highly venomous tropical American snake, Trimeresurus (or Bothops) atrox, with a greyish-brown mottled coloration: family Crotalidae (pit vipers) 矛头蛇; 产于美洲热带，剧毒