Commemoration (noun)

1. The act of remembering or honoring a person or event, typically with a ceremony or observance.
2. The act of remembering or honoring a person or event, typically with a ceremony or observance, in order to keep the memory alive and remind people of the significance of the person or event.

Origin:

From latin commemoratio, from commemorare ("to remember"), from com- ("together") + memorare ("to recall"), from memor ("mindful").

Examples:

1. The commemoration of the war was held on Veterans Day.
2. The ceremony was a commemoration of the anniversary of the founding of the city.
3. The commemoration was held to honor the victims of the tragedy.
4. The government organized a commemoration of the national hero.
5. The commemoration was held to remember the fallen soldiers.