Remembrance (noun)

1. The act of remembering or the state of being remembered.
2. Something that helps one remember a person or event, such as a keepsake or memorial.

Origin:

From the old french remembrer, from re- meaning "again" and member meaning "to remember".

Examples:

1. She kept the photograph as a remembrance of her mother.
2. The ceremony was held in remembrance of those who died in the war.
3. The memorial was built as a remembrance of the victims.
4. The company held an event in remembrance of its founder.
5. The holiday was established as a national day of remembrance.