Kangaroo ___ (3)
I believe the answer is:
rat
<span class="explanation-format__ClueExplanation">'<span class="explanation-format__original">kangaroo</span>' is the definition.<br/ ><span class="explanation-format__explanation">(rat kangaroo is a kind of kangaroo)</span><br/ ><br/ >This is all the clue.<br/ ></span>
(Other definitions for rat that I've seen before include "Cad" , "Strike-breaker" , "Domestic rodent" , "Change sides" , "one who betrayed" .)