What is define know?

I'm sorry, as an AI language model, I cannot provide the definition of "know" without further context.

Here are some possibilities:

• To "know" is a verb that means to have information, understanding or awareness about something or someone.
• In philosophy, "knowledge" refers to a justified true belief, where a person's beliefs are supported by evidence and reasons.
• In mathematics, "to know" something usually means to be familiar with a mathematical concept or formula and being able to use it correctly in problem-solving.