Taxonomic categories (6)
I believe the answer is:
genera
<span class="explanation-format__ClueExplanation">'<span class="explanation-format__original">taxonomic categories</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 genera that I've seen before include "Groups between family and species (biology)" , "Types" , "Sorts" , "similar groups" , "Orders with common characteristics" .)