Bloody hard yakka mate, bloody oath it was
In A Dictionary of Austral English, 1898, yakka is defined as:
Yakka, v. frequently used in Queensland bush-towns. "You yacka wood? Mine, give 'im tixpence;" - a sentence often uttered by housewives. It is given by the Rev. W. Ridley, in his 'Kamilaroi, and other Australian languages,' p 86. as the Turrubol (Brisbane) term for work, probably cognate with yugari, make, same dialect, and yengga, make, Kabi dialect, Queensland. It is used primarily for doing work of any kind, and only by English modification (due to 'hack') for cut. The spelling yacker is to be avoided, as the final r is not heard in the native pronunciation.
And, as with yabber, so it was initially. However, in the modern day lingo, yakka exclusively refers to bloody hard work. And generally in the phrase, "bloody hard yakka". It no longer means to cut. It is no longer used as a noun, "I have some yakka for you", as it once was. Unlike yabber, which is heard as frequently as any English word, yakka is used less and less, although it is still alive. It is quite possible that it was given a breath of life in the 1980's with a successful television advert that featured the line, "Hard Yakka - Australians have always known it".
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