Green’s Dictionary of Slang

1. (US Und.) the cold tea or coloured water drunk in the guise of ‘whiskey’ by bar-girls.

1933

(con. late 19C) H. Asbury Barbary Coast 289: Most of [the girls] ordered whisky — and were served the usual jigger of cold tea or colored water, called in this period a Kelly.

2. (Aus.) an axe; thus swing kelly, to swing an axe [brandname of Kelly Axe Manufacturing Co., Charleston, West Virginia].

[1902		Worker (Wagga, NSW) 16 Aug. 6/1: It’s the same routine here daily— you must swing your Kelly axe, / Or your Collins, or whate’er you like to call it].
1908		Worker (Wagga, NSW) 1 Oct. 13/4: It takes something to keep men up in the freezing cold of a Bowen Downs winter [...] after nine hours swinging ‘Kelly’.
1916		Bombola Times (NSW) 2 June 2/5: THE SPORT OF THE WEEK. ANZACS SWINGING ‘KELLYS’ IN FRANCE. WOOD-CHOPPING CONTESTS.
1921		Burrowa News (NSW) 7 Oct. 2/3: The district also boasts a resident 92 years of age [...] who can still swing Kelly and read the paper unaided by glasses.
1937		Western Mail (Perth) 4 Nov. 12/2: The Kelly Swingers [...] Further to the axemen series. I have been swinging Kelly on and off for 27 years, and I have come in contact with many good axemen.
1945		Baker Aus. Lang. 78: Kelly and douglas, an axe (from the names of makers), with their derivatives to swing kelly or douglas, to do axework.
1948		Worker (Brisbane) 9 Aug. 2: [photo caption] Bill Raddatz [...] unloading logs for the lads who swing the Kelly at the Exhibition chop.
1950		Western Mail (Perth) 16 Feb. 7/1: I have cleared quite a fair acreage in the wheatbelt myself in days gone by when forest country was cleared the hard way by ‘swinging the Kelly’.
1968		(con. 1928) S. Gore Holy Smoke 94: I s’pose a man ’d better be reckoning on a bit of shut-eye, if he’s going to be any good on the kelly in the morning.
1999		G. Seal Lingo 139: A kelly is the axeman’s term for his instrument, from a brand name.

3. (Aus.) a bus or tram inspector [the bushranger Ned Kelly (1855–80); like him the inspectors pounce suddenly on their victims].

1946		Tribune (Sydney) 9 Aug. 7/2: An anonymous letter writer may report to the department that Conductor ‘Jones,’ from a certain depot, is not collecting all the fares. Kelly’ Gets Busy. An examiner (‘Kelly’ to the men) is put on the job by Head Office [...] He joins Conductor ‘Jones’’ tram at some point on the run and checks the tickets.
1953		Baker Aus. Speaks.
1980		C. James Unreliable Memoirs 155: The inspectors were called Kellies, after Ned Kelly, and were likely to swoop at any time.

4. money [play on colour Kelly green].

2005

B. Hare Urban Grimshaw vii: Kelly Money.