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A long extinct dinosaur related to the Tyrannosaurus Rex and the Blundering Counter-strike Noob.

Used to express extreme pleasure or humor at something.

Related in morphology to roflcopter, rofliron, and lollerskates.
Eric: lmaosaurus! can you believe how stupid those slashdotters are?!

Tommy: roflcopter, theyre the biggest NOOBZ ever!

Eric: lollerskates, ur rite man
by Eric Goedtel October 27, 2005
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