filicidePronunciation: /ˈfɪlɪsʌɪd/Definition of filicide noun [mass noun] the killing of one’s son or daughter:maternal filicide [count noun] a person who kills their son or daughter. Origin: mid 17th century from Latin filius 'son', filia 'daughter' + -cidefilicide in other Oxford dictionaries Definition of filicide in the US English dictionary