costiero

Costiero is a term used in several Romance languages to indicate something related to the coast. It functions primarily as an adjective in Spanish, Portuguese, and Italian, and is generally translated into English as coastal. In Italian, costiero is the standard masculine adjective; as a noun, costiera denotes a coast or coastal region (for example, la Costiera Amalfitana). In Spanish, the corresponding adjective is costero (with feminine costera); in Portuguese, cognate forms exist to convey the same sense and are used in phrases like zona costiera or região costeira. The root is Latin costa, meaning side or edge, extended by metaphor to describe the edge of land along the sea.

The word appears across fields such as geography, ecology, urban planning, and tourism. It is common in geographic descriptions and official designations, with phrases like línea costera, zona costera, or região costeira. In coastal studies, costiero terms help describe features such as coastlines, beaches, mangroves, and coastal ecosystems, as well as human settlements and infrastructure along the shore. In Italy, the feminine costiera is used for regions along the coast, as in Costiera Amalfitana, a well-known coastal area.

Related terms include coast, litoral, and littoral, which describe similar coastal concepts in different languages.