Green’s Dictionary of Slang

(orig. Aus.) to smell unpleasant, to stink; often intensified as honk like a gaggle of geese.

1966		Baker Aus. Lang (2nd edn).
1978		P. Theroux Picture Palace 78: Standish, who positively honked with confidence, was good at everything.
1984		P. Slabolepszy ‘Over the Hill’ in Mooi Street (1994) 56: (Charlie is splashing on the aftershave) steve: You going to honk like a moffie.
1994		J. O’Connor Secret World of the Irish Male (1995) 229: The guy behind the counter has the worst bad breath [...] he really does honk like he ate a broiled skunk sandwich.
2003		N. Griffiths Stump 133: Yer pure rank. I’m tellin yeh, it’s that fuckin arm; it honks.
2007		A. Guthrie Hard Man 219: The inside of the car didn’t honk of dog so badly now.
2012		R. Milward Kimberly’s Capital Punishment (2023) 420: [of a corpse] By tomorrow morning, she’ll be honking.