Affect just a little (5)
I believe the answer is:
touch
This clue is a double definition.
'affect' is the first definition.
(I know that affect is a more specific form of the action the touch)
'a little' is the second definition.
(eg 'a little too big' means 'a touch too big')
'just' is the link.
(Other definitions for touch that I've seen before include "Hint" , "off pitch" , "Graze" , "Compete with" , "To ask for loan" .)