Fish-eggs (3)
I believe the answer is:
roe
I believe this clue is a double definition.
'fish' is the first definition.
(I know that roe is a type of fish)
'eggs' is the second definition.
(fish eggs)
(Other definitions for roe that I've seen before include "A mass of fish-eggs" , "eg Caviare" , "Food from fish" , "Part of fish, sounds like go through water" , "Lobster's ripe ovary" .)