1. To declare or affirm solemnly and formally as true
   "Before God I swear I am innocent";
   - affirm, verify, assert, avow, aver
    
2. Utter obscenities or profanities
   "The drunken men were swearing loudly in the street";
   - curse, cuss [informal], blaspheme, imprecate, eff [Brit, informal], eff and blind [Brit]
    
3. Promise solemnly; take an oath
   "The new citizens swore allegiance to their adopted country"
    
4. Make a deposition; declare under oath
   "The witness swore before the court";
   - depose, depone [archaic]
    
5. Have faith or confidence in
   "I swear by this brand of coffee";
   - count, bet, depend, rely, bank, look, calculate, reckon

Derived forms: swears, sworn, swore, swearing

See also: swear off [informal]

Type of: declare, express, give tongue to, pronounce, trust, utter, verbalise [Brit], verbalize, vow

Encyclopedia: Swear