Color (4)
I believe the answer is:
tint
'color' is the definition.
(I know that color is a is a more specific form of the action of tint)
This is the entire clue.
(Other definitions for tint that I've seen before include "work for coiffeuse?" , "(Softer variety of) colour" , "A slighth shade of colour" , "Hair dye" , "Quality of colour" .)