fehaciente - reliable, irrefutable, dependable, verifiedSpanish example: A veces pienso que la prueba más fehaciente de que existe vida inteligente en el universo es que nadie ha intentado contactar con nosotros.
English example: Sometimes I think that the most reliable proof that there exists intelligent life in the universe is that no one has tried to contact us.
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fehaciente - reliable, irrefutable, dependable, verified