Green’s Dictionary of Slang

nause n.

[abbr. SE nausea/nauseating]

the problem, the difficulty, the annoying thing.

[UK]G.F. Newman Villain’s Tale 56: That weren’t all though, Jack. It fucked up this one I was going after, that’s the nause.
[UK]J. Sullivan ‘It’s Only Rock and Roll’ Only Fools and Horses [TV script] They’re both broke! I’ll have to get a firm in – naus innit, eh?
[UK]Indep. Sport 4 Dec. 16: The nause is complete when I get home and discover the message facility [...] must have bust.