privity \PRIV-i-tee, noun:

1. Participation in the knowledge of something private or secret, especially as implying concurrence or consent.
2. Private or secret knowledge.
3. Law. The relation between privies.
4. Obsolete. Privacy.

Kazbitch — at least I imagine so — thought that Azamat had robbed him of his horse, with his father’s privity and consent.
— Mikhail Y. Lermontov, A Hero of Our Own Times

But Judith had not meddled with the arrangement, and every necessary disposition was made without her privity or advice.
— James Fenimore Cooper, The Leatherstocking Tales

Privity stems from the Old French words prive meaning “private, close friend, private place.”