第一背鳍
/ˈfɜːst ɐsˈɪstənt ˈkamɹəɹ ˈɒpəɹˌeɪtə/
n
English: first dorsal fin · 第一背鳍
释义：Swimming appendage formed of a membrane and usually prickly rays located on the middle anterior dorsal portion of the body; it provides stability.
English: first dorsal fin · 第一背鳍