Crown princess (皇太子妃)
The crown princess is a person who has the position of the wife of a prince.
Princess Masako, the wife of Imperial Prince Naruhito, holds that position in Japan as of 2009.
Summary
In Wago (words of Japanese origin), they were called 'Hitsuginomikonomime'. Crown princess corresponds to the Imperial Princess (Articles 5 and 6 of Imperial House Law) and is regarded as a member of the imperial family. The title of honor is 'Imperial Highness' (Clause 2 of Article 23 of the Law). It is written as Imperial Princess in Kotofu (the genealogy of the Imperial Family).
If the crown princess is a member (imperial princess or princess) of the imperial family before marriage, she continues to have the original position as well as crown princess after marriage (until she becomes an empress).
Example: Princess (Kuni no miya) Yoshiko -> Emperor Showa's Crown Princess Yoshiko -> Empress Yoshiko -> Empress Dowager Yoshiko -> Empress Kojun (posthumous title)
Today, the crown princess becomes an empress when the crown prince ascends the throne.
The crown princess loses the social status as the member of the imperial family and the position of crown princess if any of the conditions shown below is met.
(Article 14 of the Law)
The crown prince dies and the crown princess desires to leave the status of the Imperial Family member.
The crown prince dies and unavoidable special circumstances exist and the Imperial Household Council approves.
The crown princess divorces the crown prince
The formal representation (description in official gazettes, such as cabinet notifications and Imperial Household Agency notifications) by the government is 'crown prince xx imperial princess xx'. However, 'crown princess' is used on the website of the Imperial Household Agency which emphasizes the 'intelligibility to the general public' and in tree-planting ceremonies and floral tributes, and 'Princess Togu' is also used in New Year Imperial Poetry Reading.
The wife of crown prince in other countries may have a title of crown princess.