bernicle
/ˈbɜːrnɪkəl/
noun
- A small marine crustacean that attaches itself to rocks, ship hulls, and other surfaces, often causing fouling.
- The bottom of the boat was covered in barnacles, so we had to scrape them off.
- The rocky shore was dotted with barnacles and seaweed.
- Barnacles can slow down a ship by increasing drag in the water.