Green’s Dictionary of Slang

roaring fou n.

[fou adj.1 ]

a drinking spree.

[UK]Vanbrugh Provoked Wife III ii: Then up with Alley, quoth Crumma, we’s get a roaring fou.
[Scot]Burns ‘Tam O’Shanter’ in Works (1842) 67: The smith and thee gat roaring fou on.