Honor killing, most often, the murder of a woman or girl by male family members. The killers justify their actions by claiming that the victim has brought dishonor upon the family name or prestige. Britanica
Or
An honour killing or shame killing is the murder of a member of a family, due to the perpetrators' belief that the victim has brought shame or dishonour upon the family, or has violated the principles of a community or a religion, usually for reasons such as divorcing or separating from their spouse, refusing to enter an arranged, child, or forced marriage, being in a relationship or having associations with social groups outside the family that is strongly disapproved by one's family, having premarital or extramarital sex, becoming the victim of rape or sexual assault, dressing in clothing, jewelry and accessories which are deemed inappropriate, engaging in non-heterosexual relations or renouncing a faith Wikipedia:Honor killing
Honor killing is not death to preserve honor, but rather inflicting death on another to preserve familial honor.
I thought I had found two examples of honor killing in ancient literature, although people online have disagreed with me.
In Livy, the killing of Verginia by her father Verginius in ancient Rome might have been fictional, but was probably at least based on events that had actually occurred. So the issue would be whether when something like the Verginius episode did happen, it fits the modern definition of honor killing.
Whether or not the Odyssey is fictional, would an event like Telemachus's killing of the woman slaves who were disloyal to Odysseus be considered an honor killing? (Telemachus does give his "honor" as a reason for hanging them rather than killing them with a sword).
Also, there's at least one other kind of honor killing in modern times: the killing of a family member who rejects the family religion. Is there any example of this in ancient history as well?
Wikipedia gives some background, saying, for one thing, that the killing is a protection of the honor of a family. But if there are historians who have made a special study of honor killing and know whether or not the concept and practice have or have not changed over the centuries, I would prefer to go by their definitions.