According to the strict definition, the name 'Sai naishinno' was designated as a princess of blood while a female relative of the Emperor was referred to as 'Saio' or 'Saijoo,' and in general, they were collectively called Saio.
厳密には内親王なら「斎内親王」、女王の場合は「斎王」「斎女王」と称したが、一般に両者をまとめて斎王と呼ぶ。