A time when all boys involved produce their ball sack. Usually started by someone shouting-
'What time is it?'
and everyone else responding-
'Ball Bag Time'
Only done when drunk and in a crowded pub or to annoy a girlfriend.
Lout 1 'Hey james you got the time?'
Lout 2 'err, yeah its... 12:25'
Lout 1 'i think your wrong'
Lout 2 '?'
Lout 1 'I think its Ball Bag Time'
Lout 2 *looks down*