Farm building not likely to collapse (6)
I believe the answer is:
stable
'farm building' is the definition.
(I know that stable is a type of farm building)
'not likely to collapse' is the wordplay.
I cannot really understand how this works, but
'likely to' could be 'able' (I've seen this in another clue) and 'able' is found within the answer.
The remaining letters 'st' is a valid word which might be clued in a way I don't understand.
This may be the basis of the clue (or it may be nonsense).
Can you help me to learn more?
(Other definitions for stable that I've seen before include "Firm - building for animals" , "Animal accommodation is steady" , "container for punch, for instance" , "farm building" , "Standing firm" .)