Green’s Dictionary of Slang

gat n.2

[Afk. gat, hole, vent]

(S.Afr.) the buttocks, the anus; esp. as an excl.

[SA]B. Simon ‘Outers’ Born in the RSA (1997) 45: Ja, lift your alie man, lift your gat. [Ibid.] 62: You lie man. You talk through your gat.
[SA]P. Slabolepszy ‘Smallholding’ in Mooi Street (1994) 188: I was looking forward to kicking a bit a’ black gat.
[SA] (con. late 1940s) J.M. Coetzee Boyhood (1998) 57: Then there are gat and poep-hol and words like them, hurled back and forth in bouts of abuse.

In compounds

gat-creep (v.) (also gatkruip) [i.e. arse creep under arse n.]

(S.Afr.) to toady to; thus gat-creeper, a sycophant.

[SA]P. Slabolepszy Sat. Night at the Palace (1985) 12: If it’s one thing I can’t handle it’s a gat-creeper. Bloody schloep.
Weekly Mail (S.Afr.) 27 Jan. 23: An Afrikaffer is somebody who isn’t afraid to throw a rasta out of his flat [...] It’s when you’ve got past the stage of gatkruiping blacks [DSAE].
[SA]R. Malan My Traitor’s Heart 211: A few months back, he was on gatkruip patrollie, meaning ‘ass-creep patrol’ [...] Ass-creep patrol is the hearts and minds aspect of riot control in South Africa.