Top Definition
An exclamation when someone has a problem (related to math or not) and can't seem to solve it, a phrased taken from the sheer noobishness of someone and the lack of ability of doing math
Dude what is the derivative of

√(x^2 + 4x - 9) / (5x^3 - 8 x^2 +3x)

IDK, just foil :D
by moneybird1122 November 17, 2009
5 Words related to Just foil

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