Strikes lightly (4)
I believe the answer is:
taps
'strikes lightly' is the definition.
('tap' can be a synonym of 'strike lightly')
This is the entire clue.
(Other definitions for taps that I've seen before include "Bugs (wire)" , "Military bugle call at dusk" , "They're faucets in America" , "Military signal to turn the lights out" , "Military signal and faucets" .)