Daks is an Australian word for trousers and is used in exactly the same context as trousers (eg work daks, suit daks), jeans (daks) or bottoms (trackie daks, pyjama daks).
It is slang and in common use is Australia.
I am interested to know where this word comes from: Type of cloth used long ago? Particular style of trousers that was once very popular? Something else?
Does any one know? Any ideas?
(also while searching for an answer on this I read that New Zealanders take daks to mean underpants)
The company name Daks apparently came from Da(d) + (sla)cks.
That last cite from Private Eye is from the Barry McKenzie comic strip, written by the Australian writer Barry Humphries (Dame Edna), dealing with the adventures of an Aussie in London. This shows the word had entered Aussie slang by at least 1970.