When validate first entered the language in the mid-17th century, its meaning was tied fast to its close relative, the adjective valid: to validate something, such as a marriage or treaty, was to make it legally valid. This meaning is still current, but the word is now used in nonlegal and informal contexts. If the museum you visit validates your parking ticket, the museum official marks the ticket and you do not have to pay for parking. If someone's claims cannot be validated, those claims cannot be confirmed. And if a coach puts an untested player into the game and the player scores the winning point, the player's strong performance validates the coach's decision.