The small bits of excrement that stick to your arse hair. This can be reduced if not eradicated by wiping your arse properly. Restricting your intake of vindaloos and hot kebabs will reduce the likelyhood of suffering from rugnuts. As will getting a crack wax.

Also see 'Klingons'.
"Please do not be alarmed by my squirming vicar, I'm suffering from a bad case of rugnuts".

"Excuse the smell Jeremy, I have a bad batch of rugnuts".
by _Jas_ August 24, 2006
Get the rugnuts mug.
Act of hog-tying one, male or female, and dragging them across a shag carpet stomach down until orgasm is achieved.
"Bro, this chick had me burning last night, worst rugnut I ever had.
by mrpoopoopeepeedunkcacinoalapac December 13, 2021
Get the rugnut mug.