Know n. : Knee.

Know v. i. : To perceive or apprehend clearly and certainly; to understand; to have full information of; as, to know one's duty.

Know v. i. : To be convinced of the truth of; to be fully assured of; as, to know things from information.

Know v. i. : To be acquainted with; to be no stranger to; to be more or less familiar with the person, character, etc., of; to possess experience of; as, to know an author; to know the rules of an organization.

Know v. i. : To recognize; to distinguish; to discern the character of; as, to know a person's face or figure.

Know v. i. : To have sexual commerce with.

Know v. i. : To have knowledge; to have a clear and certain perception; to possess wisdom, instruction, or information; -- often with of.

Know v. i. : To be assured; to feel confident.

Example:
How much should your significant other Know about your past relationships?

Taxonomy
Merriam-Webster Online Dictionary, Dictionary, webster, Word Games, Webster Online Dictionary with audio pronunciations, thesaurus, Middle English, Old English, glossary, english, language, ESL, Search, Inflected, Etymology, Old High German, Latin, noscere.

Defination from the web:
know from the Merriam-Webster Online Dictionary with audio pronunciations, thesaurus, Word of the Day, and word games. ... 2 a : to be aware of the truth or factuality of : be convinced or certain of b : to have a practical understanding of <knows how to write> ...