WordWeb Online

1. Informal intensifier
   "what a effing nuisance"
   - bally [Brit], blinking [Brit], bloody, blooming [Brit], crashing, flaming, freaking

1. [Brit, vulgar] Have sexual intercourse with
   "This student effs everyone in her dorm"
   - sleep together, love, make out, make love, sleep with, have sex, know [archaic], do it, be intimate, have intercourse, lie with [archaic], bed, have a go at it, get it on, bonk [Brit], make whoopee
    
2. Utter obscenities or profanities
   "The drunken men were effing loudly in the street"
   - curse, cuss, blaspheme, swear, imprecate, eff and blind [Brit]

See also: unmitigated

Type of: copulate, couple, express, give tongue to, mate, pair, utter, verbalise [Brit], verbalize

Encyclopedia: Eff Eff, Marry, Kill