Chinese style posthumous name - Kanfuushigo

...A name given after death based on a person's deeds while alive. Originally a uniquely Chinese custom, it has also been practiced in Japan since ancient times due to its influence. Duan Yutai believes that the correct spelling should be "謚". There is a legend that the Gongdan of Zhou and Taigong Wang discussed and created the posthumous name system, but Guo Moruo dates its origins back to the Warring States period. It was customary for posthumous names to be bestowed by the emperor, and a posthumous name containing the character for "literature" was considered an honor. There are also other names such as private posthumous names and monk posthumous names. Nickname (Azana) Imina (Imina) [Katsumura Tetsuya]
[Japan]
It is also called a posthumous name. It was adopted in Japan in the second half of the 7th century, and bestowing posthumous names became one of the Emperor's great prerogatives.

*Some of the terminology explanations that refer to "Han-style posthumous names" are listed below.

Source | Heibonsha World Encyclopedia 2nd Edition | Information

…生前の行跡に基づいて死後に贈られた名をいう。もとは中国独自の風習であったが，その影響で日本でも古代から行われた。正しくは謚と書くべきだというのが段玉裁の説。周公旦と太公望が議して諡法を作ったという伝承があるが，郭沫若はその起源を戦国時代にまで下げる。天子より賜るのが習いで，文の字を入れた諡が名誉とされた。別に私諡，僧諡などがある。字（あざな）諱（いみな）【勝村 哲也】
［日本］
　諡号（しごう）ともいう。7世紀の後半に至って日本でも採用され，諡を贈ることは天皇の大権の一つとされた。…

※「漢風諡号」について言及している用語解説の一部を掲載しています。

出典｜株式会社平凡社世界大百科事典 第２版について | 情報