A chandelier (/ˌʃændəˈlɪər/) is an ornamental lighting device, typically with spreading branched supports for multiple lights, designed to be hung from the ceiling. Chandeliers are often ornate, and they were originally designed to hold candles, but now incandescent light bulbs are commonly used, as well as fluorescent lamps and LEDs.

A wide variety of materials ranging from wood and earthenware to silver and gold can be used to make chandeliers. Brass is one of the most popular materials, but glass is most commonly associated with chandeliers. Classic glass and crystal chandeliers have arrays of hanging "crystal" prisms to illuminate a room with refracted light. Contemporary chandeliers may assume a more minimalist design, and they may illuminate a room with direct light from the lamps or are equipped with translucent glass shades covering each lamp. Chandeliers produced nowadays can assume a wide variety of styles that span modernized and traditional designs or a combination of both.

Although chandeliers have been called candelabras, chandeliers can be distinguished from candelabras which are designed to stand on tables or the floor, while chandeliers are hung from the ceiling. They are also distinct from pendant lights, as they usually consist of multiple lamps and hang in branched frames, whereas pendant lights hang from a single cord and only contain one or two lamps with few decorative elements. Due to their size, they are often installed in large hallways and staircases, living rooms, lounges, and dining rooms, often as focus of the room. Small chandeliers can be installed in smaller spaces such as bedrooms or small living spaces, while large chandeliers are typically installed in the grand rooms of buildings such as halls and lobbies, or in religious buildings such as churches, synagogues or mosques.

The word chandelier was first known in the English language in the sense as used today in 1736, borrowed from the word in French that means a candleholder. It may have been derived from chandelle meaning "tallow candle", or chandelabre in Old French and candēlābrum in Latin, and ultimately from candēla meaning "candle". In the earlier periods, the term "candlestick", chandelier in France, may be used to refer to a candelabra, a hanging branched light, or a wall light or sconce. In English, "hanging candlesticks" or "branches" were used to mean lighting objects hanging from the ceiling until chandelier began to be used in the 18th century.

In France, chandelier still means a candleholder, and what is called chandelier in English is lustre in French, a term first used in the late-17th century. The French lustre, from Italian lustro, can also be used in English to mean a chandelier hung with crystals, or the glass pendant used to decorate such chandelier. The use of words for indoor lighting objects can be confusing, and a number of terms like lustres, branches, chandeliers and candelabras were used interchangeably at various times, which can make the early appearance of these words misleading. Girandole was also once used to refer to all candelabra as well as chandelier, although girandole now usually means an ornate branched candleholder that may be mounted on a wall, often with a mirror. Chandeliers may sometimes be called suspended lights, although not all suspended lights are necessarily chandeliers.

Hanging lighting objects, some described as chandeliers, were known since ancient times, and circular ceramic lamps with multiple points for wicks or candles were used in the Roman period. The Roman terms lychnuchus or lychnus can refer to candlestick, floor lamps, candelabra, or chandelier. By the 4th century, terms such as coronae, phari, pharicanthari were used, and they were often mentioned as presents of the popes.

In the Byzantine period, flat circular metallic structures suspended with chains that can hold oil lamps known as polycandela (singular polycandelon) were commonly used throughout the eastern Mediterranean. First developed in late antiquity, polycandela were used in churches and synagogues, and took the shape of a bronze or iron frame holding a varying number of globular or conical glass beakers provided with a wick and filled with oil. They may be hung between columns, over the altar or tombs of saints. Polycandela were also commonly used to furnish households up until the 8th century.

Hanging lamps were commonly found in mosques in Islamic countries, while sanctuary lamps were found in churches. In Iberia, which had significant Moorish influence, artisans produced hanging farol lanterns in pierced brass, bronze, and glass, alongside sanctuary lamps. A type of Spanish silver lampadario with an elongated central reservoir for oil may have developed into a form of chandelier that has a central baluster and branching arms.