galley, adj. — Green’s Dictionary of Slang

galley adj.

also gallery

[Scot. galliard, cheerful, lively]

(Irish) cheerful, fun.

1997		Share Slanguage 104: galley [...] gay, cheerful, lively.
2001		G. Coughlan Everyday Eng. and Sl. 🌐 Gallery (n): great fun, someone is a gallery-entertaining person – a mad laugh.