Green’s Dictionary of Slang

1. (Aus.) a scheme, a plot, a plan.

1888

‘Rolf Boldrewood’ Robbery Under Arms (1922) 36: You haven’t got to do with the old-fashioned mounted police that was potterin’ about when this ‘bot’ was first hit on.

2. (Aus./N.Z., also bott) a cadger, a scrounger, a hanger-on.

1916		All Abaht It Nov. 24: The bogey will be picqueted and lit in time for the ‘Bot’s fatigue’.
1919		W.H. Downing Digger Dialects 13: bott — (1) A cadger; (2) a useless person; (3) a hanger-on.
1924		(con. WWI) A.G. Pretty Gloss. of Sl. [...] in the A.I.F. 1921–1924 (rev. t/s) n.p.: bott. (1) A cadger; a hanger on.
1941		Baker N.Z. Sl. 51: By the 1920’s a bot is being used extensively for a troublesome person, for a persistent borrower, a financial parasite. [...].
1943		Baker ‘Influence of American Sl. on Australia’ in AS XVIII:4 255: Here are a few of the items included: [...] bot, a persistent borrower.
1968		(con. 1928) S. Gore Holy Smoke 93: Don’t go around dookin’ a few bob to every bot that puts the hard word on yer.
1983		R. Aven-Bray Ridgey-Didge Oz Jack Lang 15: His acting the purse man brought the place to life. The bots ordered up only the best brands of lunatic soup from the top shelf.

3. (Aus./N.Z.) a germ; thus phr. of greeting, how are the bots biting?

1914		Sport (Adelaide) 12 June 4/3: They Say [...] Ruggy Joe caught the bot through all the flies following him.
1941		Baker N.Z. Sl. 51: In early uses bot is rendered as a germ, doubtless from bot-fly. From this comes the phrase of greeting, How are the bots biting? By the 1920’s a bot is being used extensively for a troublesome person, for a persistent borrower, a financial parasite. [...] Of fairly recent development in New Zealand is the phrase to have the bot, to be sick or out of sorts, moody or disagreeable.
1972		G.W. Turner Eng. Lang. in Aus. and N.Z. 109: A germ going around is usully a bot in New Zealand.
1988		McGill Dict. of Kiwi Sl. 19/1: bot a germ, originally in 1920s a TB patient, latterly a minor ailment, usually cold or flu; probably derived from the botfly, whose larvae feed beneath the skin, an afflicter of horses. – to have the bot to feel unwell or irritable. – how’re the bots biting? a humorous greeting.
1999		B. Bova Return to Mars 492: ‘How’re the bots biting?’ ‘Bots?’ ‘Insects,’ she said. ‘No bites,’ Jamie answered. ‘No insects.’.
2003		McGill Reed Dict. of N.Z. Sl. [as cit. 1988].