privy

1. sharing in the knowledge of (something secret or private).

   he was no longer privy to her innermost thoughts

2. hidden; secret.

   a privy place

1. a toilet located in a small shed outside a house or other building.
2. a person having a part or interest in any action, matter, or thing.

Middle English (originally in the sense ‘belonging to one's own private circle’): from Old French prive ‘private’ (also used as a noun meaning ‘private place’ and ‘familiar friend’), from Latin privatus ‘withdrawn from public life’ (see private).