Young pilchard (7)
I believe the answer is:
sardine
<span class="explanation-format__ClueExplanation">'<span class="explanation-format__original">young pilchard</span>' is the definition.<br/ ><span class="explanation-format__explanation">(I've seen this in another clue)</span><br/ ><br/ >This is the entire clue.<br/ ></span>
(Other definitions for sardine that I've seen before include "Fish in tin?" , "Small fish, usually canned" , "Swimmer" , "FRENCH FISH" , "Stonefish OR? Stone" .)