Himemiko (Imperial Princess) (皇女)
Himemiko (also referred to as Ojo or Kojo) is the naming of daughters of Tennoo (emperor). It was a status of the female Imperial Family members, before the establishment of the title of Naishino (imperial princess). Meanwhile, the sons of the emperors were called Miko (imperial prince). Shifting from it, the Himemiko is also used to call the daughters of the sovereigns of other countries other than Japan (example; Anastasia Nikolaeva Romanova).
Himemiko (Imperial Princess)
Originally, the children of Gozoku (local ruling family) were widely called 'Miko' in the period of Yamato sovereignty, and while the naming came to refer to the children of Okimi (great king of Yamato sovereignty), the daughters of Okimi came to be called 'Himemiko.'
And, the characters of 皇女 came to be applied for Himemiko, along with the establishment of Tenno (emperor).
However, Miko and Himemiko stopped to be used as the naming of the specific imperial children, upon the establishment of Shino (imperial prince) and Naishino as the statuses of the emperors' children. But, it remained as the customs to generally call the emperors' daughters Himemiko, which became to be often used to refer to their relationship with the emperors as the first Himemiko, second Himemiko.
Especially in the society of nobles, the genealogy of the maternal line was a criterion of prosperity of the family and promotions; and the ones whose mothers were Naishino were described as Mikobara (children by Himemiko) and regarded as the children of noble birth, along with Kisaibara (children by empress).
Today, "Himemiko" is also often used to stress a situation of specific Imperial Family such as 'The tragic Himemiko, Kazunomiya Chikako Naishino' (the Imperial Princess Kazunomiya Chikako) apart from the names or statuses of the members of the Imperial Family.