Arthropods (7)
I believe the answer is:
insects
<span class="explanation-format__ClueExplanation">'<span class="explanation-format__original">arthropods</span>' is the definition.<br/ ><span class="explanation-format__explanation">(I know this)</span><br/ ><br/ >This is all the clue.<br/ ></span>
(Other definitions for insects that I've seen before include "Ants, say" , "Small invertebrate creatures" , "Small arthropods" , "Bugs" , "Six-legged creatures" .)