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1.
A reply to a statement implying that what was said is an untruth.
Does not need to be used as a response only to untruths but can also be used to point out ridiculous or silly statements which may or may not be true.
Person 1: " 'Got milk?' was my idea!"
Person 2: " Ombongo!"
by Aluvia Saccharide November 29, 2010