Pet rodent (7)
I believe the answer is:
hamster
<span class="explanation-format__ClueExplanation">'<span class="explanation-format__original">pet rodent</span>' is the definition.<br/ ><span class="explanation-format__explanation">(I've seen this before)</span><br/ ><br/ >This is all the clue.<br/ ></span>
(Other definitions for hamster that I've seen before include "Rodent often kept as pet" , "Furry pet" , "The arms (anag)" , "Short-tailed burrowing rodent" , "Little beast" .)