A party celebrating the last night of freedom of a man before he gets married, but where another man steals the limelight/tries to convince everyone its his own party. The term is commonly used in the west of Ireland.
1) Wow! I'd say Barry was well annoyed at that Paddy Stag last weekend in Cork.

2) Jaysus, the DJ announced another blokes name instead of Baz! It must be Paddy's Stag!
by logger mclog May 17, 2010
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