Privy

adj. confidential, secret; clandestine, covert; sharing a secret; private, intended only for a particular individual

n. lavatory, crude outdoor toilet, outhouse; (Law) person who has an interest or participates in something that involves a third party

The term privy now refers to an outhouse.However, it is used with a different meaning in the term Privy council.privy adj 1 : personal, private 2 : secret 3 : admitted as one sharing in a secret
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Noun
1. a room equipped with toilet facilities
(synonym) toilet, lavatory, lav, can, john, bathroom
(hypernym) room
(hyponym) head
(part-meronym) toilet, can, commode, crapper, pot, potty, stool, throne
2. a small outbuilding with a bench having holes through which a user can defecate
(synonym) outhouse, earth-closet, jakes
(hypernym) outbuilding
Adjective
1. hidden from general view or use; "a privy place to rest and think"; "a secluded romantic spot"; "a secret garden"
(synonym) secluded, secret
(similar) private
2. (followed by `to') informed about something secret or not generally known; "privy to the details of the conspiracy"
(synonym) privy(p)
(similar) informed

(n.)
A partaker; a person having an interest in any action or thing; one who has an interest in an estate created by another; a person having an interest derived from a contract or conveyance to which he is not himself a party. The term, in its proper sense, is distinguished from party.
  

(n.)
A necessary house or place; a backhouse.
  

(a.)
Secret; clandestine.
  

(a.)
Of or pertaining to some person exclusively; assigned to private uses; not public; private; as, the privy purse.
  

(a.)
Appropriated to retirement; private; not open to the public.
  

(a.)
Admitted to knowledge of a secret transaction; secretly cognizant; privately knowing.
  

A latrine or bathroom. In a castle called a garderobe.