40-ouncer colloquial; 40-ouncer, forty-ouncer, forty ouncer DCHP-2 (February 2016)
n. — slang, informal
a bottle of 40 fluid ounces of liquor.
Type: 5. Frequency — In Canada, spirits are sold in 40-ounce containers. While in the US bottles of the same size are sold as well, the term is nearly twice as frequent in Canadian English as in American English. The spelling with the numeral 40 is more common compared with forty.
See also COD-2, which marks the term "Cdn slang".
See also: two-six
- In spoken language often just referred to as "a forty" (see 2014 quotation).
- 1972  Add another 50 cents per passenger for free booze (four doubles of good rye which the airline can buy at under $2 tax-free for a 40-ouncer), a bit more than that for mixers and a dollar or two for food -- which can vary greatly -- and you come up with one price just over $50 and the other a few dollars under. For a round trip. 
- 1978  Before setting the Texaco fire Mr. Coxhead had downed the better part of a "40-ouncer" of rye." 
- 1988  Drinks are simple. The outdated old Canadian standard for liquids was the mickey, the bottle, and the forty-ouncer. With metric, they changed all the stores so you can pick your own size right off the shelf -- mickey, bottle, or 40-ouncer, as modern as tomorrow with the metric contents in very small print on the label. 
- 1990  The man said he was in with about 34 other inmates, about 12 of whom were out "on pass" at any one time. The "pass" inmates would smuggle drugs and booze into the jail, he said.
"There was more drugs in there than booze. But you could always get a 40 ouncer of Bacardi rum (white). I have seen bottles of Bacardi rum. [...]" 
- 2001  "It started with a pint a day," says Jane. "Then a forty ouncer a day. And he gambled all day and night. He hardly ever stepped away from the video lottery machine." 
- 2002  Another witness said she paid Martinez $110 for a 40-ouncer of vodka while he was driving for the Nanook taxi company on Aug 13, 2001. 
- 2008  "Somebody smashed out the big window in the front of the store and got four bottles of Bacardi Rum -- two 66 ouncers and two 40 ouncers." 
- 2014  As Jamie Q. lay in a hospital bed suffering from pancreatitis, the nurse asked his former wife if he drank.
"He may have a beer or two," she answered.
The last words that Jamie said before he fell unconscious were: "I drink a forty a day." 
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Chart 1: Internet Domain Search, 21 Sep. 2012