It is said that 'Sei Shonagon' denotes her as a lady of the court and that 'Sei' refers to her family name of KIYOHARA, while 'Shonagon' is the name of her relative's bureaucratic post.
「清少納言」は女房名で、「清」は清原の姓から、「少納言」は親族の役職名から採ったとされている。