From Wiktionary, the free dictionary
nick off (third-person singular simple present nicks off, present participle nicking off, simple past and past participle nicked off)
- (Australia, slang) To leave, especially in a hurry.
1961, Nene Gare, The Fringe Dwellers, Text Classics, published 2012, page 338:‘I got somethin ta tell ya. Young Trilby's knicked off.’
1965, Mudrooroo, Wild Cat Falling, HarperCollins, published 2001, page 64:I'm in for the strap tomorrow anyway when Dickie sees my sums. Got to nick off now.
nick off
- (UK, Australia) Go away; get lost.