verb (v)

• approve and express assent, responsibility, or obligation(verb.social)

  Synonym:
  sign
  

  source: wordnet30
• To approve and sanction; to make valid; to confirm; to establish; to settle; especially, to give sanction to, as something done by an agent or servant; as, to ratify an agreement, treaty, or contract; to ratify a nomination.(verb)

  source: webster1913