Sighted (6)
I believe the answer is:
espied
<span class="explanation-format__ClueExplanation">'<span class="explanation-format__original">sighted</span>' is the definition.<br/ ><span class="explanation-format__explanation">(espying is a kind of sighting)</span><br/ ><br/ >This is all the clue.<br/ ></span>
(Other definitions for espied that I've seen before include "Watched" , "observed in literature" , "Glimpsed" , "Saw (archaic)" , "Caught sight of (archaic)" .)