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- a social occasion with special entertainments or performances（有特别娱乐或表演的）聚会：
as modifier a gala performance by the Royal Ballet.皇家芭蕾舞团的特别演出。
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- Brit. a special sports meeting, especially a swimming competition〈英〉专项运动会（尤指游泳比赛）。
词源
early 17th cent. （in the sense 'showy dress'）： via Italian and Spanish from Old French gale 'rejoicing'.