Applies lightly (4)
I believe the answer is:
dabs
'applies lightly' is the definition.
(I've seen this in another clue)
This is all the clue.
(Other definitions for dabs that I've seen before include "Small quantities of liquid" , "Fish < experts" , "Fingerprints (sl.)" , "Fingerprints (colloq.)" , "incriminating evidence, perhaps" .)