What does "jetty" mean?

Jetty: (Arch.) A part of a building that jets or projects beyond the rest, and overhangs the wall below.

Additional senses

  1. 2.A wharf or pier extending from the shore.
  2. 3.(Hydraul. Engin.) A structure of wood or stone extended into the sea to influence the current or tide, or to protect a harbor; a mole; as, the Eads system of jetties at the mouth of the Mississippi River. Jetty ad (Naut.), a projecting part at the end of a wharf; the front of a wharf whose side forms one of the cheeks of a dock.
  3. 4.To jut out; to project. [Obs.] Florio. JEU D'ESPRIT Jeu" d'es`prit". Etym: [F., play of mind.] A witticism.

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