barnacle

/ˈbɑrnəkəl/

/ˈbɑnəkəl/

Other forms: barnacles

A barnacle is a spineless animal that looks like a small circular white rock. You'll often find barnacles attached to the bottom of boats.

Barnacles are crustaceans, which means they're related to crabs, lobsters, and shrimp, all of which have an external shell. In the case of barnacles, their shells attach to things like rocks, other shells, docks, and boats, and stay there permanently, filtering food from shallow ocean water through feathery appendages. The earliest use of the word referred to a European goose whose mythology described it hatching from the marine crustacean that eventually took its name.

Definitions of barnacle

1. noun

   marine crustaceans with feathery food-catching appendages; free-swimming as larvae; as adults form a hard shell and live attached to submerged surfaces
   synonyms: cirriped, cirripede

   types:

   Balanus balanoides, acorn barnacle, rock barnacle

   barnacle that attaches to rocks especially in intertidal zones

   Lepas fascicularis, goose barnacle, gooseneck barnacle

   stalked barnacle that attaches to ship bottoms or floating timbers

   type of:

   crustacean

   any mainly aquatic arthropod usually having a segmented body and chitinous exoskeleton
2. noun

   European goose smaller than the brant; breeds in the far north
   synonyms: Branta leucopsis, barnacle goose

   type of:

   goose

   web-footed long-necked typically gregarious migratory aquatic birds usually larger and less aquatic than ducks