know vs tell apart

know is a noun but tell apart is not a noun.

Word	Noun	Adjective	Verb	Adverb
know	Yes	No	Yes	No
tell apart	No	No	Yes	No

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

Other hypernyms of know include differentiate, distinguish, secern, secernate, separate, severalise, severalize, tell.

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

know (verb)	tell apart (verb)
be familiar or acquainted with a person or an object	mark as different
be cognizant or aware of a fact or a specific piece of information; possess knowledge or information about	detect with the senses
know how to do or perform something
have firsthand knowledge of states, situations, emotions, or sensations
accept (someone) to be what is claimed or accept his power and authority
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