knifefish
/ˈnaɪffɪʃ/noun
(复同单, 或-fishes)
1- a semi-nocturnal freshwater fish with a reduced or absent dorsal fin and a long anal fin which reaches from the belly to the tail宝刀鱼:
1.1
- a New World fish with a narrow eel-like body (families Rhamphichthyidae and Gymnotidae: several genera).宝刀鱼(吻电鳗科、裸背电鳗科: 数属)。
1.2
- another term for FEATHERBACK.