noun
A public event
A formal act
ceremony refers to a formal, usually solemn, act established as proper to some religious or state occasion the ceremony of launching a ship; rite refers to the prescribed form for a religious ceremony or procedure burial rites; ritual refers to rites or ceremonies collectively, esp. to the rites of a particular religion the ritual of voodooism, and in extended use is applied to a regularly repeated act or series of acts performed in a set, ceremonial manner bedtime rituals; formality suggests a conventional, often meaningless, act or custom, usually one associated with social activity the formalities of polite conversation
See ceremony in Webster's New World Roget's A-Z Thesaurus II
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