interlink vs join

interlink is not a noun while join is a noun.

Word	Noun	Adjective	Verb	Adverb
interlink	No	No	Yes	No
join	Yes	No	Yes	No

As verbs, join is a hypernym of interlink; that is, join is a word with a broader meaning than interlink:

Other hypernyms of interlink include connect, link, link up, unite.

interlink (noun)	join (noun)
	a set containing all and only the members of two or more given sets
	the shape or manner in which things come together and a connection is made

interlink (verb)	join (verb)
cause to be interconnected or interwoven	make contact or come together
be interwoven or interconnected	cause to become joined or linked
	become part of; become a member of a group or organization
	come into the company of
	be or become joined or united or linked