Dictionary

To perceive the truth or factuality of; to be certain of or that.

Example: He knew something terrible was going to happen.

To be aware of; to be cognizant of.

Example: Did you know Michelle and Jack were getting divorced? ― Yes, I knew.

To be acquainted or familiar with; to have encountered.

Example: I know your mother, but I’ve never met your father.

To experience.

Example: Their relationship knew ups and downs.

Any fact or situation which is known or familiar.

A constant or variable the value of which is already determined.

Identified as a specific type; famous, renowned.

Example: He was a known pickpocket.

Accepted, familiar, researched.