Unspecified large number (7)
I believe the answer is:
umpteen
<span class="explanation-format__ClueExplanation">'<span class="explanation-format__original">unspecified large number</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 umpteen that I've seen before include "Plentiful" , "Informally, very many" , "Lots of things on pet menu" , "Unspecified large number" , "Great in number but unspecified" .)