adjoin vs butt

adjoin is not a noun while butt is a noun.

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

As verbs, adjoin and butt are synonyms defined as:

Other synonyms of adjoin include abut, border, butt against, butt on, edge, march.

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

adjoin (noun)	butt (noun)
	thick end of the handle
	the small unused part of something (especially the end of a cigarette that is left after smoking)
	a large cask (especially one holding a volume equivalent to 2 hogsheads or 126 gallons)
	sports equipment consisting of an object set up for a marksman or archer to aim at
	finely ground tobacco wrapped in paper; for smoking
	a joint made by fastening ends together without overlapping
	the fleshy part of the human body that you sit on
	a victim of ridicule or pranks
	the part of a plant from which the roots spring or the part of a stalk or trunk nearest the roots

adjoin (verb)	butt (verb)
attach or add	to strike, thrust or shove against
lie adjacent to another or share a boundary	place end to end without overlapping
be in direct physical contact with; make contact	lie adjacent to another or share a boundary