Sweeper collects everything in the hall (8)
I believe the answer is:
ballroom
'hall' is the definition.
(I've seen this before)
'sweeper collects everything' is the wordplay.
'sweeper' becomes 'broom' (a broom sweeps things up).
'collects' means one lot of letters goes inside another.
'everything' becomes 'all' (all things).
'broom' going around 'all' is 'BALLROOM'.
'in the' is the link.
(Other definitions for ballroom that I've seen before include "potential murder scene on board" , "Place for old-fashioned dancing - and romance?" , "hop in here?" , "Dance venue" , "Hall for dancing" .)