What is the meaning of privy?

noun

• A room or building equipped with one or more toilets.
  • synonyms: toilet, lavatory, lav, can, john, bathroom
• A small outbuilding with a bench having holes through which a user can defecate.
  • synonyms: outhouse, earth-closet, jakes

adjective

• Hidden from general view or use.
  • usage: "a privy place to rest and think"; "a secluded romantic spot"; "a secret garden"
  • synonyms: secluded, secret
• Followed by `to'. ( informed about something secret or not generally known)
  • usage: "privy to the details of the conspiracy"