Synonymous with complete failure despite supreme confidence. In perhaps the biggest upset in Super Bowl history, the NY Giants defeated the heavily favored New England Patriots who entered Super Bowl XLII with a perfect 18-0 record. So sure of themselves, the Patriots filed applications to patent the phrase "19-0" and "19-0 The Perfect Season" more than a week before the game, only to have their collective asses handed to them by the Giants.

see also ryan leaf
(failing a final exam despite having an A average going in) Boy, I really went "18 and 1" on that exam.

(losing the war in Iraq despite superior force going in) When will Bush ever realize that we went "18 and 1" in Iraq?
by SaMo Snatcher February 5, 2008
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to work at something and nearly accomplish something great, before failing at the end
Jimmy had an 'A' going into the final exam, but did poorly and therefore, went 18 and 1 in the class.

Entemology: The Patriots were undefeated going into the Super Bowl, but went 18 and 1 for the season.
by D. J. (from PSU) February 4, 2008
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Joe thought the night was going good for him but he turned out just to be 18 and 1.
by Your Name, really February 4, 2008
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18 n 1 When your are close to accomplishing an amazing feat and choke near the finish
Bobby almost got his Degree but pulled a 18 n 1
by mike karate February 25, 2008
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A feat achieve by the San Francisco 49ers, Chiacgo Bears, and New England Patriots.
The San Francisco 49ers went 18-1 and won the Super bowl.

The Chicago Bears went 18-1 and won the Super bowl.

The New England Patriots went 18-1 and lost the Super bowl. Sucka!
by Eagles 2011 SB Champs December 16, 2010
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1. The biggest upset in football history (used by patriots fans)

2. The greatest thing to happen to the planet since boobs. (used by everyone else)
1. I can't believe the patriots only got 18-1. That's bullshit!

2. WOO-HOO!!! 18-1, SUCK ON THAT, BRADY!!!
by James Tinman February 4, 2008
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The New England Patriots had their hopes of completing a perfect season destroyed by losing the one game that counts: The Super Bowl.

Not only that, but they were also caught cheating during the season so even if they went 19-0 it would still always be questioned.
by I'm some chick February 4, 2008
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