Maritime Glossary


Islands of America is an ongoing education—it’s akin to pursuing a Masters degree without formal faculty or classrooms, but rather hundreds of experts and lab experiments. All specialized fields have their own lexicons; here is a handful of formal and colloquial terms I’ve encountered from the 100 or so collected. (You’re welcome, Scrabble® enthusiasts.)


BAFFLE Designed to shield people from excessive noise and associated with foghorns, these artificial sound barriers can also serve to conceal submarines and other Navy vessels from detection. One example stands on Burrows Island, Washington.

BORTLE SCALE Experienced comet and star observer John E. Bortle developed a system to rate, on a scale of one to nine, light pollution that affects visibility in the nocturnal sky. He presented the Bortle Dark-Sky Scale in Sky & Telescope magazine defining each level by the celestial features that should be visible to the naked eye. Class 1 is the darkest sky, with no light from the moon or artificial sources obscuring the view. A typical rural setting, with distant light pollution, rates as Class 3, while a brightly lit urban environment is a Class 9. Islands, set apart from mainlands, have a built-in Bortle Scale advantage.

CONCH Originally a colonial slang term for Bahamians of European descent, Bahamian descendants in the Keys also referred to themselves as conchs; now, it’s a term for any resident of Key West. The flag of The Conch Republic (created for a secession movement) features a conch shell.

DENE A bare, sandy tract or low sand hill near the sea; a dune.

EYOT Pronounced “ait,” (an alternate spelling) eyots are islets or small islands in rivers. Eyots usually grow from sediment, may be either permanent or temporary and tend to have long, slender shapes. The term is used especially to describe many of the small, upstream islands in England’s River Thames.

GABION A rock-filled wire mesh “cage” placed at the upper part of sandy beaches to defend against wind and wave erosion.

HOLM A small riverine or lake island, or a flat piece of land next to a river, creek, stream or other running water; appears in the names of several European islands, including Flat Holm and Steep Holm in England’s Bristol Channel.

JETSAM With its origin in the word “jettison” this refers to anything deliberately thrown from a sailing vessel including ballast, cargo or equipment discarded during storms. Jetsam may either float to shore or sink on the spot but can be taken by anyone who finds it, unless the owner files a claim. In the Keys, a famous example is marijuana packs referred to as “square grouper” that are thrown overboard when law enforcement is near.

LITTORAL The coastal habitat between the high- and lowwater marks of a lake, ocean or sea. In coastal areas it’s found between the supralittoral zone, the area above the water line but affected by spray and mist from the water, and the sublittoral zone which extends from the low-water line to depths of more than 650 feet. Plant species in littoral zones may include cattails, rushes and water lilies, while animals such as crabs, snails, turtles and wading birds live and feed in this habitat. 

MIDDEN A pile of shells discarded after consumption of shellfish; archeologists use middens as part of their excavation studies to determine native habitation. They aren't only a thing of the past, though—in Aquinnah on Martha's Vineyard, Massachusetts the Wampanoag tribe's scallop middens are still built.

OSIITUH The Gullah term for oyster as heard on Daufuskie Island, South Carolina and Sapelo Island, Georgia.

PEELERS The name for a softshell crab on Smith Island, Maryland and other areas in and near the Chesapeake.

PICAROON Scoundrels and rogues, especially pirates.

TOMBOLO These sandbars or sand spits form a natural bridge between an island and the mainland or between two islands. Tombolos often develop when currents deposit sediment in shallow channels.

WRACK The seaweed and other dead vegetation that washes ashore, often indicating high-water and daily high-tide marks.