Pest is abandoned in shade (6)
I believe the answer is:
nuance
'shade' is the definition.
('nuance' can be a synonym of 'shade')
'pest is abandoned' is the wordplay.
'pest' becomes 'nuisance' (I've seen this before).
'abandoned' indicates named letters should be taken away.
'nuisance' with 'is' removed is 'NUANCE'.
'in' acts as a link.
(Other definitions for nuance that I've seen before include "Ace nun (anag)" , "Subtlety, nicety" , "Cue Ann into slight shade" , "Delicate shade of difference" , "Fine distinction" .)