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1. [Brit, vulgar] Have sexual intercourse
   - 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, make whoopee, nail [N. Amer]
    
2. Utter obscenities or profanities
   "The drunken men were effing loudly in the street";
   - curse, cuss, blaspheme, swear, imprecate, eff and blind [Brit]

Derived forms: effs, effed, effing

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

Encyclopedia: Eff