Prove (verb)

1. Establish the truth or genuineness of (something) by presenting evidence.
2. Test (something) in order to establish its quality, or the genuineness of something.

Origin:

Middle english from old french probar from latin probare to prove, from probus good.

Examples:

1. The evidence proves beyond doubt that he is guilty.
2. I need to prove my identity before I can collect my package.
3. The experiment was conducted to prove the theory.
4. She proved to be a valuable asset to the company.
5. I can't prove it, but I'm convinced he's lying.