1. 鳃裂：鳃弓之间形成5对鳃裂(gill cleft),鳃裂内、外分别开口于咽部及鳃腔(软骨鱼类直接开口体表),硬骨鱼类的鳃腔外覆有鳃盖骨(内缘附有鳃盖膜),以一总的鳃孔(gill opening)通向体外.
2. 鳃孔：gill 鳃 | gill cleft 鳃孔 | gill cover 鳃盖
noun
1. one of a series of slit openings in the pharynxes of fishes and aquatic amphibians through which water passes
Synonym: gill slit branchial cleft