Carnival (see other spellings and names) is a Western Christian and Greek Orthodox festive season that occurs before the liturgical 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 celebrations, including events such as parades, public street parties and other entertainments, combining some elements of a circus. Elaborate costumes and masks allow people to set aside their everyday individuality and experience a heightened sense of social unity. Participants often indulge in excessive consumption of alcohol, meat, and other foods that will be forgone during upcoming Lent.
Other common features of carnival include mock battles such as food fights; expressions of social satire; mockery of authorities; costumes of the grotesque body that display exaggerated features such as large noses, bellies, mouths, 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.
The term Carnival is traditionally used in areas with a large Catholic presence, as well as in Greece. The Philippines, a predominantly Roman Catholic country in Asia, also celebrates Carnival (or Mardi Gras). In historically Evangelical Lutheran countries, the celebration is known as Fastelavn, and in areas with a high concentration of Anglicans (Church of England / Episcopal Church in the U.S.A.), Methodists, and other Protestants, pre-Lenten celebrations, along with penitential observances, occur on Shrove Tuesday. In Slavic Eastern Orthodox nations, Maslenitsa is celebrated during the last week before Great Lent. In German-speaking Europe and the Netherlands, the Carnival season traditionally opens on 11/11 (often at 11:11 a.m.). This dates back to celebrations before the Advent season or with harvest celebrations of St. Martin's Day.
The Latin-derived name of the holiday is sometimes also spelled Carnaval, typically in areas where Dutch, German, French, Spanish, and Portuguese are spoken, or Carnevale in Italian-speaking contexts. Alternative names are used for regional and local celebrations.
Folk etymologies state that the word comes from the Late Latin expression carne levare, which means "farewell to meat", signifying the approaching fast. The word carne may also be translated as flesh, producing "a farewell to the flesh", a phrase embraced by certain carnival celebrants to embolden the festival's carefree spirit.  The etymology of the word Carnival thus points to a Christian origin of the celebratory period.
Other scholars argue that the origin is the festival of the Navigium Isidis ("ship of Isis"), where the image of Isis was carried to the seashore to bless the start of sailing season. The festival consisted of a parade of masks following an adorned wooden boat, called in Latin carrus navalis, possibly the source of both the name and the parade floats.
The word Carnival is of Christian origin, and in the Middle Ages, it referred to a period following Christmastide that reached its climax before midnight on Shrove Tuesday. Because Lent was a period of fasting, "Carnival therefore represented a last period of feasting and celebration before the spiritual rigors of Lent." Meat was plentiful during this part of the Christian kalendar and it was consumed during Carnival as people abstained from meat consumption during the following liturgical season, Lent. In the last few days of Carnival, known as Shrovetide, people confessed (shrived) their sins in preparation for Lent as well. In 1605, a Shrovetide play spoke of Christians who painted their faces to celebrate the season: