Top definition
Able to prove that a number like pi or √2 cannot be expressed as a ratio of two whole numbers—that they are irrational numbers.
An early sign to assess a student's mathematical maturity is to test whether he is irrational or not.
by MathPlus September 13, 2016
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2
1) refusing something rational
2) refusing all things rational
3) unreasonable, not reasonable
4) refusing logic, illogical
5) unwilling to see the perfectoin of my logic and desperately clinging to quaint notions or antiquated superstitions that are nullified by the enfoulabilidy of my vastly superior position, absolutely infallible perfection
"You continue to disagree with me, despite having heard all the facts of the matter, which indicates you are either daft or irrational."
by kplugrafa September 10, 2009
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3
Guy: That's a very poor decision...
Girl: I'm irrational.
by BigSlice July 27, 2008
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4
The belief of Mets fans that they will ever win a game
"Yo dude, how are the Mets gonna do this season?"
"World series in six! You can't beat a core offense with Wright, Reyes, Beltran, and Bay!"

(Five months later, 17 games back in the NL East, irrational hope still exists)
by yagottabelieve April 17, 2010
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