noun, masculine/ku.jɔ̃/plural: couillons
testicle; dickhead, bastard, pillock; coward; a Belgian card game also played in Limburg and on the border of Luxemburg and Germany; joker, funny person; nut, nutter
“Il t'a vraiment trompée ? J'étais sûr que c'était un couillon, ce type.” — He really cheated on you? I knew that guy was a bastard.
Synonyms: couille
Inherited from Middle French couillon, from Old French coillon (“testicle”), from Late Latin cōleōnem, derived from Latin cōleus (“sack, bag; scrotum”). By surface analysis, couille + -on. Compare Occitan colhon.