In traditional arts such as music and dance, a student who has learned a certain level of skill may receive a professional name from the head of the school, the iemoto. This is called natori, taking a name.
The Nipponica encyclopedia says that the iemoto gives the disciple some characters of the school’s name. As a rule, the iemoto receives a substantial sum and issues a certificate and a name plate. A natori may then take disciples and teach them as the iemoto’s representative.