Gumtree

An Australian 'buy and sell' style website, that tried to expand overseas but didn't go great because no-body knew what a Gumtree was.

A: You know where I can get the used mattress of a meth addict?
B: Have you tried Gumtree?

140 gumtree drive

driving your car into a gumtree at 140 km per hour

"I just lost full custody man, gonna take the ute down 140 gumtree drive."

Gumtree

What grows inside you when you swallow gum

Example 1:
Man 1: Raaa I just swallowed some gum
Man 2: fam, manna is gonna get a gumtree
Man 1: scruthers?
Man 2: still

Officer: Sir, please don't spit out your chewing gum
Roadman: or what blad? allow man getting a gumtree
Officer: Sir, will I need to hand you a caution?
Roadman: Bun your caution, man aint no lyax (spits and books)

Gumtree plumber

A plumber that advertises on Gumtree, looking to scrape clients from the bottom of the barrel . Due to low overheads, (usually still lives at home with mum & dad) can beat any price by reputable plumbing businesses. Installs all types of plumbing fixtures always asks for cash and never puts in any tickets.
Usually has the words Cheap, Affordable or discount in the business name.

Hey George did you get that quote to install the toilet from yesterday?
No mate owners wanted a Gumtree plumber, bloke did it for $49, but they’ll keep our number and call us in a few months to come by and repair it.