swear - verb

• utter obscenities or profanities
• to declare or affirm solemnly and formally as true
• promise solemnly; take an oath
• make a deposition; declare under oath
• have confidence or faith in

swear - thesaurus

affirm   assert   aver   avow   bank   blaspheme   curse   cuss   depone   depose   imprecate   rely   swan   trust   verify