Pulling a Bridget happens when someone pays for everyone's bill at the pub and gives the waiter a crazy large tip.
Below is an example of Pulling a Bridget:

Person: I'll take the bill for my table, please.
Server: Your bill has been taken care of.

Person: What, really? Who paid!? May I leave you a tip?
Server: You can if you want to, but please know that your friend pulled a Bridget.
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