Ceviche, cebiche, sebiche, or seviche (Spanish pronunciation: [seˈβitʃe]) is a cold dish consisting of fish or shellfish marinated in citrus and seasonings. Different versions of ceviche are part of the culinary cultures of various Latin American countries along the Pacific Ocean where each one is native, including Chile, Colombia, Costa Rica, Ecuador, El Salvador, Guatemala, Honduras, Mexico, Puerto Rico, Nicaragua, Panama, and Peru. Ceviche is considered the national dish of Peru and is recognized by UNESCO as an expression of Peruvian traditional cuisine and an Intangible Cultural Heritage of Humanity.

The fish or shellfish in ceviche is not served raw like sashimi; the citric acid from the citrus marinade causes the proteins in the seafood to become denatured, resulting in the dish appearing to be "cooked" without the application of heat. The fish is typically cured in lemon or sour lime juice, although sour orange was historically used. The dressing also includes some local variety of chili pepper or chili, replaced by mustard in some parts of Central America. The marinade usually also includes sliced or chopped onions and chopped cilantro, though in some regions such as Mexico, tomatoes, avocadoes, and tomato sauce may be included.

Ceviche is often eaten as an appetizer; if eaten as a main dish, it is usually accompanied by side dishes that complement its flavors, such as sweet potato, lettuce, maize, avocado, or fried plantains, among various other accompaniments.

The first documented evidence of the term ceviche is from 1820, in the patriotic song "La Chicha," considered the first Peruvian national anthem.

According to the Royal Spanish Academy, the word might have the same etymology as the Spanish term escabeche, which derives from Mozarabic izkebêch, in turn descending from Andalusian Arabic assukkabáǧ, which also derives from Classical Arabic sakbāj (سكباج, meaning meat cooked in vinegar). It is ultimately from the unattested Middle Persian *sikbāg, from sik ("vinegar") and *bāg ("soup"), which also yielded the Persian word sekbā (سکبا, a soup made with meat and vinegar). Another hypothesis is that it derives from the Quechua word siwichi, meaning fresh fish.

The name of the dish is spelled variously as cebiche, ceviche, seviche, or sebiche, but the most common spelling is ceviche with v, such as in Peru, which is an alternative spelling accepted by the Royal Spanish Academy. There are also other local variants of the name, including cerbiche and serviche.

Various explanations of the dish's origins exist, with Peruvian researchers favoring a pre-Hispanic origin. According to some historic sources from Peru, the Caral civilization that developed in central Peru between 3500 BC to 1800 BC has left evidence of the use and consumption of raw Peruvian anchovy with chili and salt, according to the investigations of archaeologist Ruth Shady. Another predecessor of ceviche originated among the Moche, a coastal civilization that began to flourish in present-day northern Peru nearly 2,000 years ago. The Moche used the fermented juice from the local banana passionfruit. Recent investigations further show that during the Inca Empire, fish was marinated with chicha, an Andean fermented beverage. Different chronicles also report that along the Incan coast before the arrival of Spaniards, fish was consumed with salt and ají.

The dish is popular in the Pacific coastal regions of western South America. The technique of macerating raw fish and meat in vinegar, citrus, and spices (escabeche) was brought to the Americas from Spain and is linked to the Muslim heritage in Spanish cuisine. However, archeological records suggest that something resembling ceviche may have been indigenous to western South America as early as 2,000 years ago.