Cocktail ingredient? (5)
I believe the answer is:
prawn
<span class="explanation-format__ClueExplanation">'<span class="explanation-format__original">cocktail ingredient?</span>' is the definition.<br/ ><span class="explanation-format__explanation">(I've seen this before)</span><br/ ><br/ >This is the entire clue.<br/ ></span>
(Other definitions for prawn that I've seen before include "Large shrimp" , "Shellfish" , "Small tasty crustacean, nice in cocktail" , "basis for cocktail" , "Bit of seafood" .)