Inherited fromMiddle Frenchcouillu, fromOld Frenchcoillu, fromVulgar Latin*cōleūtus. CompareSpanishcojudo. Bysurface analysis,couille +-u.
couillu (femininecouillue,masculine pluralcouillus,feminine pluralcouillues)
FromOld Frenchcoillu.
couilluneeds inflection