Difficult to carry round store (5)
I believe the answer is:
hoard
'store' is the definition.
(I know this)
'difficult to carry round' is the wordplay.
I cannot quite see how this works, but
'round' could be 'o' (round can mean a round object) and 'o' is found within the answer.
'difficult' could be 'hard' (associated in meaning) and 'hard' is located in the remaining letters.
No letters remain.
This may be the basis of the clue (or it may be nonsense).
(Other definitions for hoard that I've seen before include "Store of treasure" , "Accumulated store" , "Collection" , "Hidden stock" , "Stash of treasure" .)