Green’s Dictionary of Slang

gagging for phr.

also gagging to
[SE gag, to choke]

desperate for/to.

[Ire]J. O’Connor Secret World of the Irish Male (1995) 74: I [...] was gagging for another bottle of Moroccan Beaujolais.
[UK]N. Barlay Curvy Lovebox 115: I can’t breathe an’ I’m gaggin’ for charlie.
[UK](con. 1979–80) A. Wheatle Brixton Rock (2004) 194: If he pressed home his advantage, Flynn would be gagging to use his blade.
[UK]Eve. Standard mag. 23 Feb. 42: By the last race I was gagging for a win.
[Aus] www.thepantsman.com 🌐 Most lady friends are hesitant at first to experience the hydration mask (but always end up gagging for it).
[Aus]L. Redhead Cherry Pie [ebook] After a couple of decades with a squishy, golf playing investment banker I’d be gagging for a bit of well-built rough trade.
[Ire]L. McInerney Glorious Heresies 302: ‘Look, I’m gagging, Ryan, if you can even give me a number . . .’.

In phrases

gagging for (it) (also gagging, gagging on it)

desperate for sex; usu. but not invariably of a woman.

[Scot]I. Welsh Trainspotting 200: There’s foreign fanny aw ower the place, some ay them gaggin oan it.
[UK]Observer Mag. 11 July 28: They are gagging for it, she led me on, Your Honour, she was deliberately inciting me.
[UK]J. Poller Reach 92: Sad, single women, who are [...] in their parlance ‘gagging for a shag’.
[UK]N. Griffiths Grits 189: A right goer, yull ser, gaggin fer it, yull ser.
[UK]J. Meades Empty Wigs (t/s) 767: ‘On a scale of one to five where five is total willing to go all the way, gagging for it, you’re making the running...’.