In idle moment, raise lute to play (2,7)
I believe the answer is:
at leisure
'in idle moment' is the definition.
(at leisure means idly or at no particular time)
'raise lute to play' is the wordplay.
'to play' indicates anagramming the letters.
'raise'+'lute'='raiselute'
'raiselute' anagrammed gives 'AT LEISURE'.
(Other definitions for at leisure that I've seen before include "'Marry in haste, repent . . . . . . . . . '" , "free" , "Relaxing, not working" , "in an unhurried fashion" , "No hurry, having a rest" .)