Canadian slang is like the people, friendly, slightly apologetic, and surprisingly hardcore when you least expect it. A toque, a double-double, and a "sorry" will get you through most situations, eh.
Toque
A knitted winter hat. Americans call it a beanie, Brits say woolly hat, but in Canada it's a toque (say "took") and it's basically a national uniform from October to April.
Double-double
A coffee with two creams and two sugars from Tim Hortons. It's not just a drink order, it's a cultural institution. Ordering a double-double is basically a Canadian citizenship test.
Loonie
The Canadian one-dollar coin, named after the loon (the bird on it). Its two-dollar big brother is naturally the "toonie." Canadian money has the best nicknames in the world.
Eh
The legendary Canadian conversation tag. It turns any statement into a friendly question and any question into a shared experience. It's not just a word, it's social glue.
Hoser
A lovable loser, an unsophisticated person. Made famous by Bob and Doug McKenzie, it's the Canadian insult that's somehow affectionate. A hoser is dumb but harmless, like a golden retriever in human form.
Timbits
Donut holes from Tim Hortons. These tiny balls of deep-fried dough are essentially the Canadian communion wafer, shared among friends, available in every flavour, and sacrilegiously delicious.
Sketch
Sketchy, suspicious, untrustworthy. When something's sketch, your instincts are telling you to back away slowly. It's the Canadian shorthand for "this doesn't feel right."
Boonies
The middle of nowhere, the rural backcountry, way out in the sticks. If you're in the boonies, your nearest Tim Hortons is a long drive away and that's the real measure of remoteness in Canada.
Turfed
To fall hard, to wipe out, to hit the ground. Usually involves ice, because Canada. Getting turfed on a patch of black ice is practically a national rite of passage every winter.
Snowbird
A Canadian who escapes to warmer climates (usually Florida or Arizona) during winter. They migrate south like actual birds, except they're carrying golf clubs and SPF 50.
Givin'er
Going all out, giving maximum effort, sending it with everything you've got. Canadians might be polite but when they're givin'er, all restraint goes out the window.