乌燕鸥 wūyàn'ōu sooty tern Definitions Defs Origin Strokes Stroke Words Sentences Sents 乌 烏 wū noun black (bound form) black; dark; raven-colored燕鸥 燕鷗 yàn'ōu tern A sea bird of the tern subfamily, typically having a slender beak, webbed feet, and a long forked tail. Known for their long-distance migration, most notably by the Arctic tern.