breakwater

plural breakwaters

1. A construction in or around a harbour designed to break the force of the sea and to provide shelter for vessels lying inside.

   They sailed around a breakwater that hadn't existed on Peregrine's last trip and tied in at the moorage.

   1992, Vernor Vinge, A Fire Upon the Deep, New York: Tor Books, →ISBN, →LCCN, →OCLC, page 70

   3 more examples

   […]there is a channel, some three miles wide between the city and the mainland, and some mile and a half wide between it and the sandy breakwater called the Lido, which divides the lagoon from the Adriatic,

   1853, John Ruskin, “The Throne”, in The Stones of Venice, volume II (The Sea-Stories), London: Smith, Elder, and Co., […], →OCLC, § VI, page 8

   But there's a pier or breakwater runs out into the sea just here, which we could defend longer than anything else, like Horatius and his bridge.

   1908, G[ilbert] K[eith] Chesterton, The Man Who Was Thursday: A Nightmare, Bristol: J[ames] W[illiams] Arrowsmith, […]; London: Simpkin, Marshall, Hamilton, Kent & Company, →OCLC, page 259

   Using the countless tons of rock from the cliff-face, supplemented by much more from inland, they threw out a huge breakwater, 2,000 ft. long and 80 ft. high, roughly at right angles to the quay, so forming an almost completely sheltered corner. Fifty years later, this massive mole is still standing up to the worst that the Irish Sea can do.

   1956 September, F. F. Nicholls, “Neyland, A Forgotten Harbour”, in Railway Magazine, page 632

2. nauticalA low bulkhead across the forecastle deck of a ship which diverts water breaking over the bows into the scuppers.
3. on beachesA wooden or concrete barrier, usually perpendicular to the shore, intended to prevent the movement of sand along a coast.

1. A suburb of Geelong, Victoria, Australia