Moron's equivalent for undoubtedly. Coined by Simon Cowell and used by him on a weekly basis on xfactor.
Louis: You made it your own, you have the likeability factor, you remind me of a young Chesney Hawkes.

Simon: That was undoubtably the greatest performance of "you Raise Me Up" since Westlife. You gave it 100 million percent.
by onthinice November 4, 2009
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Has the same meaning as Doubn't.
I undoubt in him! He can do it!
by Vladland September 13, 2018
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