US /ɑn ðə bʌm/
・UK /ɒn ðə bʌm/
not too tight on the belly, not too loose on the bum,
They will wear clothes that have their size, a proper cut, not too tight on the belly, not too loose on the bum, not too short if it's a top, because you don't want people to see your belly if you raise your arms,