Numbers 25:15, 18

The name of the Midianite woman who was slain was Cozbi the daughter of Zur, who was head of the people of a father’s household in Midian.

for they have been hostile to you with their tricks, with which they have deceived you in the affair of Peor and in the affair of Cozbi, the daughter of the leader of Midian, their sister who was slain on the day of the plague because of Peor.”