Incontestable (adjective)

1. Undeniable, not open to question or dispute.
2. Not capable of being challenged, opposed or refuted.
3. Facts, evidence or claims that are beyond doubt or question.

Origin:

Derived from the latin word "incontestabilis" meaning "undisputed, undeniable".

Examples:

1. The incontestable truth of evolution by natural selection.
2. His victory in the election was incontestable as the results showed a clear majority.
3. The incontestable evidence of his guilt led to his conviction in court.
4. Her achievements in the field of science were incontestable, making her a renowned expert.
5. The incontestable authenticity of the antique vase made it a valuable collectible.