Play a guitar lightly (5)
I believe the answer is:
strum
'play a guitar lightly' is the definition.
(I've seen this in another clue)
This is the entire clue.
(Other definitions for strum that I've seen before include "Casually play (on a stringed instrument)" , "Play stringed instrument with sweep of hand" , "Pluck the strings idly" , "Play with sweeps of fingers" , "Play a banjo" .)