Small telescope (8)
I believe the answer is:
spyglass
<span class="explanation-format__ClueExplanation">'<span class="explanation-format__original">small telescope</span>' is the definition.<br/ ><span class="explanation-format__explanation">(I've seen this before)</span><br/ ><br/ >This is the entire clue.<br/ ></span>
(Other definitions for spyglass that I've seen before include "lookout's aid" , "he can see through it!" , "viewer" , "Aid to pirate, perhaps" , "Small refracting telescope" .)