Garden insect (6)
I believe the answer is:
'garden insect' is the definition.
(I've seen this before)
This is the entire clue.
(Other definitions for earwig that I've seen before include "Eavesdrop (informal)" , "An insect, I wager (anag.)" , "Aural kind of insect" , "Close acquaintance" , "Small insect with pincers at end of its body" .)