Bag that’s worn-out in large room (7)
I believe the answer is:
holdall
'bag' is the definition.
(I know that holdall is a type of bag)
'worn-out in large room' is the wordplay.
'worn-out' becomes 'old' (I've seen this in another clue).
'in' indicates putting letters inside.
'large room' becomes 'hall' (a hall is a large room).
'old' going inside 'hall' is 'HOLDALL'.
'that's' is the link.
(Other definitions for holdall that I've seen before include "Handled bag" , "Capacious bag or basket" , "Bag (contents unlimited?)" , "A large soft travelling bag - stuff everything in" , "Large case, with handles" .)