Green’s Dictionary of Slang

gack n.1

also gak
[? link to dial. gack, to chatter, to talk idly, i.e. one of the drug’s primary effects]

1. (UK drugs) cocaine.

Show quotations
[UK]N. Barlay Curvy Lovebox 92: We do a couple more dabs of gak.
[UK]K. Sampson Powder 273: He took out a chubby wrap of gack. ‘. . . I’m going to cover you in cocaine . . .’.
[UK]N. Griffiths Stump 11: — Could do with a bumper of that gack of Peter’s, fuckin wake me up, like.
[UK]J.J. Connolly Viva La Madness 99: Suddenly Dougie isn’t so intoxicated by the booze, gak and pussy.
[UK]K. Sampson Killing Pool 51: The ever-present thrum of gack [...] the urgent menace of cocaine.
[Scot]I. Welsh Decent Ride 184: Ye fancy a wee bitty posh up the hooter, mate? [...] Ching. Racket. Bugle. Gak. Charlie.
[Ire]L. McInerney Blood Miracles : You can nose around a pile of gak, so long as you’re not nosing around her.

2. (US und.) dandruff.

Show quotations
[US](con. 1962) J. Ellroy Enchanters 319: He needed a whisk broom. Scalp gack dusted his suit coat.

In compounds

gackhead (n.)

an obsessive or regular user of cocaine.

Show quotations
Twitter 15 June 🌐 My favourite one [i.e. Father’s Day message] being ‘there’s no better role model for our baby boy’ - if by that you mean you want your child to be a sexaholic gak head.