they may be electric (4)
I believe the answer is:
eels
'they may be electric' is the definition.
(I've seen this in another clue)
This is all the clue.
(Other definitions for eels that I've seen before include "Long fishes" , "Elongated fish" , "Slender fishes" , "eg Conger" , "They have long bodies and very small fins" .)