Fully grown human (5)
I believe the answer is:
adult
<span class="explanation-format__ClueExplanation">'<span class="explanation-format__original">fully grown human</span>' is the definition.<br/ ><span class="explanation-format__explanation">(I've seen this in another clue)</span><br/ ><br/ >This is all the clue.<br/ ></span>
(Other definitions for adult that I've seen before include "(Of an animal) fully developed" , "Older person" , "Mature, fully grown" , "Indecent" , "I wasn't born yesterday" .)