Gnatlike insect (5)
I believe the answer is:
midge
'gnatlike insect' is the definition.
(I've seen this in another clue)
This is the entire clue.
(Other definitions for midge that I've seen before include "Tiny biting fly" , "A small biting gnat-like insect" , "Small person" , "Dipterous insect, in swarms by water" , "Small flying insect" .)