Barrier Island Definition

bărē-ər

noun

A long, relatively narrow island running parallel to the mainland, built up by the action of waves and currents and serving to protect the coast from erosion by surf and tidal surges.

American Heritage

A long, narrow island, parallel to the coastline, formed from deposits of sand and sediment thrown up by the waves, that serves the shore as a protective barrier against tidal waves, storms, etc.

Webster's New World

An island close to, and parallel to, the main coastline.

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