Definition of "kanga"

There are some 32 different terms for prison officers, from the humorously affectionate kanga(rhyming slang:kangaroo = screw) and the variants Scooby-Doo and Dr. Who via the mildly confrontational German (as if still the enemy over 50 years after World War II!) to the outright abuse of shit-parcel.

1996, Angela Devlin, Prison Patter‎, Waterside Press

So we thought there'd been trouble over there, maybe all the kangas were getting into mufti.

2002, Julian Broadhead, Laura Kerr, Prison Writing: A Collection of Fact, Fiction and Verse‎, Waterside Press, page 90

‘Fucking loony bin more like. There's no one sick here, not physically anyway. Don't worry, you'll get used to it. It's the kangas you want to watch out for.‘‘Kangas?’‘Kangaroo. Screw.’

2006 February 9, Kevin Lewis, Kaitlyn‎, Penguin UK

The kangas allow me the bottles for my ships.

2010 February 4, Michael Arditti, The Enemy of the Good‎, Quercus Publishing

They will f***ing dangle you, the kangas. [They'll] make it look like suicide.

2013, Jonathan Asser, David Mackenzie, Starred Up‎, spoken by Neville Love (Ben Mendelsohn)

Even the diversionary fracas on the far side of the room failed to divert him, although the kangas went racing across to deal with it — there was always some kind of a dust up going on.

2017 April 27, Kate Dunn, The Dragonfly‎, Aurora Metro Publications Ltd.