Find Out Meaning

(idiomatic) To discover, as by asking or investigating.

Example:   I don't know who the twenty-first president of the United States was, but it should be very easy to find out.
To discover or expose (someone) as disobedient, dishonest, etc.
  He had been fiddling the books for years, but finally he was found out.
To uncover a weakness (in someone).
  He may cope with the multiple choice questions, but the written exam will find him out.