lunk, adj. — Green’s Dictionary of Slang

lunk adj.

[Scot. lunkie, close, ult. Norwegian lunke, a tepid degree of heat]

(Irish)

1. of weather, close, sultry.

1987		T. Paulin ‘Waftage: An Irregular Ode’ in Fivemiletown 6: All of my mates / were out of town / that lunk July.
1997		Share Slanguage.

2. of a person, feeling ill.

1997