'J'

Jack

A policeman or detective; nickname for a kookaburra; a double headed penny

Jack Rice couldn't jump over Considerable ready money; a large roll of banknotes
Jack shay A tin quart pot used for boiling water or cooking in the bush or outback
Jack Smithers A lone drink or a lone drinker
Jack the painter Strong bush tea
Jack up -to- To refuse to proceed with something
Jackass -a laughing- A kookaburra
Jacked off to be tired of; to be fed up with
Jackeroo A station hand who is being trained for managerial status
Jacko A kookaburra
Jacky An aboriginal male
Jacky Howe A short-sleeved shirt favoured by shearers
Jacky raw A new chum
Jaffle -a- A toasted sandwich
Jagging -go- To make a social visit with the aim of gossiping
Jake -she's- A phrase meaning everything is ok eg "She's Jake, mate"
Jaked -it's- It's broken
Jamberoo A lively party
Jar A pint of beer
Jarrah jerker A timber getter in Western Australia
Jelly Gelignite
Jerry -to- To understand; to realise
Jewey A jewfish; a Jew lizard
Jiffy -see you in a- See you shortly
Jim The sum of £ 1
Jimmy An immigrant
Jimmy Woodser A solitary drink; a solitary drinker
Jingos -by- Expression of wonder
Job -to- To hit with the fist
Jocks Male underwear
Joe A police trooper; a penny; a snake
Joe Blake Term used in rhyming for snake 
Joe! Joe Joe! Joey! Cries of warning once widely used on goldfields to notify the approach of troopers
Joes Melancholy feelings

Joey

A baby kangaroo, also the young of other marsupials; a young child; a minor lie or evasion; a threepenny bit; something worthless; a fraud

Joey -wood and water- A handyman on a station homestead
John A policeman; a Chinese
John hop A policeman
John -the- The toilet
Johnny cake A small damper baked in the embers of a fire
Johnny Warder A lone drinker
Jollop Strong liquor
Jonah -to- To ruin; to hinder; to bring misfortune
Jonnick Right; correct; honest
Jumbuck A sheep
Jump out -the- The beginning of some activity
Jump up A mixture of flour and water boiled into paste with sugar; a sudden rise in country encountered on an outback journey
Jumper A woollen top; sweater
Junker A large conveyance with four wheels for transporting logs
Just quietly Confidentially between you and me