swear vs swear off

swear and swear off both are verbs.

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

swear (verb)	swear off (verb)
have faith or confidence in	promise to abstain from
make a deposition; declare under oath
utter obscenities or profanities
promise solemnly; take an oath
to declare or affirm solemnly and formally as true