A party is a gathering of people who have been invited by a host for the purposes of socializing, conversation, recreation, or as part of a festival or other commemoration or celebration of a special occasion. A party will often feature food and beverages, and generally conversation, music, dancing, or other forms of entertainment.

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Not who you're looking for? Others named surprise party: 1983 film by Roger Vadim

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From Wikipedia (CC BY-SA 4.0).