1, 2.See corresponding entry in Unabridgeddeception, lie, untruth, deceit. Collins Concise English Dictionary © HarperCollins Publishers:: mendacity/mɛnˈdæsɪtɪ/n(pl-ties) the tendency to be untruthful a falsehood Etymology: 17thCentury: from Late Latinmendācitās,from Latinmend...