Foetus (6)
I believe the answer is:
embryo
<span class="explanation-format__ClueExplanation">'<span class="explanation-format__original">foetus</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 embryo that I've seen before include "that develops after congress" , "Nucleus" , "Sometimes the result of an accident" , "Organism in its earliest stages of development" , "Issue conceived" .)