Spiny lobster (9)
I believe the answer is:
langouste
'spiny lobster' is the definition.
(synonyms)
This is all the clue.
(Other definitions for langouste that I've seen before include "Seafood is possibly" , "It may be eaten roasted" , "something to eat" , "One in the sea" , "Spiny lobster without large claws" .)