Australian saying, meaning "shout" drinks. To buy the round of drinks. You can shout a mate anything you like, as long as you have the money!. Works on a reciprocal system, unless your mates are tightarses
this is often done in black churches when you feel the "holy spirit". it is usually very big and draws a lot of attention. you may stomp on the floor and yell or jump up an down or number of other movements.
-girl that service was so good they had me shoutin up in there!!