Either of a pair of propositions, that cannot both be true or both be false.
That contradicts something, such as an argument.
That is diametrically opposed to something.
That is itself a contradiction.
Mutually exclusive.
Tending to contradict or oppose, contrarious.
An incommensurable value or quantity; an irrational number.
Not able to be measured by the same standards as another term in the context.
having a ratio that is not expressible as a fraction of two integers.
having no common integer divisor except 1.