purple martin

purple-martin的词性：
n.（名词）

1. A large North American swallow (Progne subis) having glossy, blue-black plumage and, in the female, a light-colored breast.
紫燕：一种长有光泽的燕黑色羽毛且雌燕长有浅色胸部的大型北美燕类（紫崖燕）