privy

(noun) a room or building equipped with one or more toilets. Synonyms: toilet, lavatory, lav, can, john, bathroom.

(noun) a small outbuilding with a bench having holes through which a user can defecate. Synonyms: outhouse, earth-closet, jakes.

(adj) hidden from general view or use. Synonyms: secluded, secret. Examples: "A privy place to rest and think." "A secluded romantic spot." "A secret garden."

(adj) (followed by `to') informed about something secret or not generally known. Synonyms: privy(predicate). Example: "Privy to the details of the conspiracy."