Fish that may be electric (3)
'fish that may be electric' is the definition.
(I've seen this in another clue)
This is all the clue.
(Other definitions for eel that I've seen before include "Slippery person" , "Fish in the Lee?" , "Large elver" , "Sea creature like conger" , "A sea snake" .)
(Other definitions for eels that I've seen before include "Sea snakes among lees" , "Slippery creatures" , "Feels small imprisoning water creatures" , "Water snakes twisting in lees" , "Slippery customers" .)