And the daughter of any priest, if she profanes herself by whoring, profanes her father; she shall be burned with fire.
Leviticus 21:9 ESV

This is about Temple prostitution. Like Nadab and Abihu, the priest's daughter offers "strange fire", making herself "set apart" in the process. Like other objects that are illicitly made holy, she is to be devoted to destruction, i.e. burned. Jewish tradition says she is to be stoned first and then her body burned, but the simple reading implies that she is to be burned to death.