swear vs utter

swear is not an adjective while utter is an adjective.

Word	Noun	Adjective	Verb	Adverb
swear	No	No	Yes	No
utter	No	Yes	Yes	No

As verbs, utter is a hypernym of swear; that is, utter is a word with a broader meaning than swear:

Other hypernyms of swear include express, give tongue to, verbalise, verbalize.

swear (adjective)	utter (adjective)
	complete and absolute
	without qualification; used informally as (often pejorative) intensifiers

swear (verb)	utter (verb)
have faith or confidence in	express in speech
make a deposition; declare under oath	articulate; either verbally or with a cry, shout, or noise
utter obscenities or profanities	express audibly; utter sounds (not necessarily words)
promise solemnly; take an oath	put into circulation
to declare or affirm solemnly and formally as true