revving, adj. — Green’s Dictionary of Slang

revving adj.

[from the ‘revolutions’ of an aeroplane engine]

(Aus.) very busy.

1919		W.H. Downing Digger Dialects 42: revving — Very busy.
1924		(con. WWI) A.G. Pretty Gloss. Sl. [...] in the A.I.F. 1921–1924 (rev. t/s) n.p.: revving. Very Busy. Adapted from the simile of the revolutions of an aeroplane propellor.