狂欢节（英语：Carnival），为期数星期至数月的重要节期，人们打扮一番后巡游庆祝，略有街头派对气氛。天主教和东正教教会并不以礼仪庆祝，而是属于信徒的民间活动；基督新教则无论教会或信徒，一般并不庆祝这个节日。举办细节（如：时间）视乎各国风俗而异，主要庆祝集中于二、三月，但通常在大斋期（四旬节）的首日─大斋首日（圣灰星期三）前结束。

除了圣诞节之外所有天主教假日均以复活节为准，每一年的复活节均是北半球春天（或南半球秋天）昼夜平分点后第一个满月之后的第一个礼拜天，回算40天就是嘉年华会的圣灰星期三。

Carnival (see other spellings and names) is a Christian festive season that occurs before the Christian season of Lent. The main events typically occur during February or early March, during the period historically known as Shrovetide (or Pre-Lent). Carnival typically involves a public celebration and/or parade combining some elements of a circus, masks and public street party. People wear masks and costumes during many such celebrations, allowing them to lose their everyday individuality and experience a heightened sense of social unity. Excessive consumption of alcohol, meat, and other foods proscribed during Lent is extremely common. Other common features of carnival include mock battles such as food fights; social satire and mockery of authorities; the grotesque body displaying exaggerated features especially large noses, bellies, mouths, and phalli or elements of animal bodies; abusive language and degrading acts; depictions of disease and gleeful death; and a general reversal of everyday rules and norms.