Green’s Dictionary of Slang

(Aus.) first-rate, excellent; also used in negative to indicate that one is not feeling well.

1969		A. Buzo Rooted III i: His Mum cooks a crash hot rissole.
1970		Aus. Women’s Wkly 14 Oct. 21/1: Gone are the endless queues [of skiers] and Crash-hot Charlie blitzing in and out of you wobbly path.
1981		Aus. Women’s Wkly 20 May 168/1: Love’s crash-hot for Ringo and Barbara.
1988		B. Humphries Complete Barry McKenzie 11: The word got around London we were onto something pretty crash-hot.
1999		Bug (Aus.) 28 July 🌐 Now which table knife do we slash our collective wrists with? Do we work from the outside in or visa versa? The Bash was never all that crash hot on haute cutlery.
2003		McGill Reed Dict. of N.Z. Sl. 54: crash hot! Exclamation of strong approval. Often used in the negative, as complaining about not feeling too crash hot to indicate you are feeling lousy. ANZ from c.1950.
2018		G. Gilmore Base Nature [ebook] ‘Don’t look so crash-hot yourself’.
2023		A. Nette Orphan Road 133: ‘You don’t look so crash hot yourself’.