Young goose (7)
I believe the answer is:
gosling
<span class="explanation-format__ClueExplanation">'<span class="explanation-format__original">young goose</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 gosling that I've seen before include "Young waterbird" , "Little bird" , "Young goose" , "Young bird" .)