imperial memorial ceremony held on fixed anniversaries
A formal ceremony conducted at the Imperial Palace on specific anniversaries (e.g., 3rd, 5th, 10th, 20th, 30th, 40th, 50th, 100th) of an emperor's or empress's death. The term is primarily used in historical and official contexts.
See also: 式年
The imperial memorial ceremony for Emperor Meiji was held at the Imperial Palace.