Dry biscuit (7)
I believe the answer is:
cracker
<span class="explanation-format__ClueExplanation">'<span class="explanation-format__original">dry biscuit</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 cracker that I've seen before include "Knockout biscuit?" , "Biscuit for cheese" , "often pulled at parties" , "Beautiful woman" , "it may be specially for Christmas" .)