realize vs know

realize is not a noun while know is a noun.

Word	Noun	Adjective	Verb	Adverb
realize	No	No	Yes	No
know	Yes	No	Yes	No

As verbs, know is a hypernym of realize; that is, know is a word with a broader meaning than realize:

realize: be fully aware or cognizant of
know: be cognizant or aware of a fact or a specific piece of information; possess knowledge or information about

Other hypernyms of realize include cognise, cognize.

As verbs, know is a hyponym of realize; that is, know is a word with a more specific, narrower meaning than realize:

realize (noun)	know (noun)
	the fact of being aware of information that is known to few people

realize (verb)	know (verb)
perceive (an idea or situation) mentally	be familiar or acquainted with a person or an object
be fully aware or cognizant of	be cognizant or aware of a fact or a specific piece of information; possess knowledge or information about
make real or concrete; give reality or substance to	know how to do or perform something
expand or complete (a part in a piece of baroque music) by supplying the harmonies indicated in the figured bass	have firsthand knowledge of states, situations, emotions, or sensations
convert into cash; of goods and property	accept (someone) to be what is claimed or accept his power and authority
earn on some commercial or business transaction; earn as salary or wages	know the nature or character of
	be able to distinguish, recognize as being different
	perceive as familiar
	have fixed in the mind
	have sexual intercourse with