Idle youngster on farm having bounds reset? (4)
I believe the answer is:
loaf
'idle' is the definition.
(loafing is a kind of idling)
I don't understand the remainder of the clue.
(Other definitions for loaf that I've seen before include "Spend time idly, having slangy head" , "Baguette or cob, perhaps" , "Bread unit" , "Suffer loss of credibility" , "bloomer, perhaps" .)