基本解释[魚] 臀鰭词组短语短語anal fin rays 臀鰭Anal fin ray 臀鰭條vent to anal fin length 排泄孔臀鰭長anal fin更多词组英英字典柯林斯英英字典 a median ventral unpaired fin, situated between the anus and the tail fin in fishes, that helps to maintain stable equilibrium anal fin剑桥字典anal fin柯林斯字典专业释义辳業科學臀鰭生物學臀鰭