adhere vs adjoin

adhere and adjoin both are verbs.

Word	Noun	Adjective	Verb	Adverb
adhere	No	No	Yes	No
adjoin	No	No	Yes	No

As verbs, adjoin is a hypernym of adhere; that is, adjoin is a word with a broader meaning than adhere:

adhere: come or be in close contact with; stick or hold together and resist separation
adjoin: be in direct physical contact with; make contact

Other hypernyms of adhere include contact, meet, touch.

adhere (verb)	adjoin (verb)
follow through or carry out a plan without deviation	attach or add
stick to firmly	lie adjacent to another or share a boundary
come or be in close contact with; stick or hold together and resist separation	be in direct physical contact with; make contact
be compatible or in accordance with
be loyal to
be a devoted follower or supporter