1. commemorate
To commemorate an important event or person means to remember them by means of a special action, ceremony, or specially created object.
e.g. The 200th anniversary of Mozart's death is being commemorated around the world with concerts featuring his work.
2. empirical
Empirical evidence or study relies on practical experience rather theories.
e.g. There is no empirical evidence to support his thesis.
3. abdicate
If a king or queen abdicates, he or she gives up being king or queen.
e.g. The last French king was Louis Philippe, who abdicated in 1848.