Green’s Dictionary of Slang

1. to belch; also as n.

1923		J. Manchon Le Slang.
1971		N. Armfelt Catching Up 12: Warwick seemed impatient to keep Graham drinking. [...] Graham gurked, and his gurk felt a bit full.
1973		J. Lees-Milne Heretics in Love 30: Star said, ‘Uncle Bertie, hiccups are funny, aren’t they?’ ‘Well, they sometimes are,’ the Colonel said. I said, ‘But gurks aren't, are they, Uncle Bertie?’ ‘No, they're unfunny’ Star said, ‘And farts aren't either, are they, Uncle Bertie?’ ‘No, they're disgusting’.

2. (Aus.) to break wind.

1941		Baker Popular Dict. Aus. Sl.
1996		D.L. Flusfeder Like Plastic 94: He odorised the room with the gay scent of last night’s vindaloo. He crepitated with joy. He gurgled with pleasure. He let rip. He gurked.