Lean against and break (4)
I believe the answer is:
rest
'lean' is the definition.
(I've seen this before)
I don't understand the rest of the clue.
Can you help me to learn more?
(Other definitions for rest that I've seen before include "Support for putting things on" , "Others; cease work" , "Tranquillity" , "still holding it" , "Calm" .)