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1. Intended as a commemoration
   "a commemorating plaque";
   - commemorative, memorial

1. Celebrate by some ceremony or observation
   "The citizens commemorate the anniversary of the revolution with a march and a parade";
   - mark
    
2. Call to remembrance; keep alive the memory of someone or something, as in a ceremony
   "We commemorated the 50th anniversary of the liberation of Auschwitz";
   - remember
    
3. Be or provide a memorial to a person or an event
   "This sculpture commemorates the victims of the concentration camps";
   - memorialize, memorialise [Brit], immortalize, immortalise [Brit]

Type of: celebrate, keep, observe, remind