Sentence:  <WSD>Familicide</WSD> is the murder of family members by another family member. In other words, <WSD>familicide</WSD> is a multiple-victim homicide in which the killer's spouse or partner and one or more children are killed. Although <WSD>familicide</WSD> is relatively rare, it is nevertheless the most common form of mass killing. 
Meaning of the word marked with <WSD> tags:  The murder of an entire family by a family member.