I would have to say that Social Wolf's explanation is closer to the defintion of gynocide, at least as it is currently being used. Both words have only begun to be used in the last decade or two and neither of them are in any dictionaries. Femicide is a term that was coined by feminists and generally used to lend political significance to the murder of a woman, such as the murder of one's wife, girlfriend, sister, mother, neighbour, etc. and often used in conjunction with the word 'intimate' to emphasize that the woman knew her killer; it is derived from the Latin word femina meaning 'woman' and the Latin caedere meaning to 'to slay', in contrast to homicide with the Latin word homo meaning 'man'.