Privy means having special knowledge about something private or secret. If you're privy to information, you know something that most people don't, often because someone trusted you enough to share it. A teacher might be privy to the principal's plans for a surprise assembly, or your older sister might be privy to your parents' anniversary gift plans.

The word suggests both knowledge and trust. When someone makes you privy to their thoughts or plans, they're letting you in on something confidential. You might say, “I'm not privy to those details” when people ask you about something you genuinely don't know.

As a noun, a privy was also a small outdoor toilet, especially before modern plumbing became common. You might encounter this meaning in old books or at historical sites. The Privy Council in England is a group of advisors to the monarch, trusted with private government matters.