barnacle
- A type of marine crustacean with a hard shell that attaches itself permanently to a variety of surfaces such as rocks, ship hulls, and even other animals. nounThe ship's hull was covered in barnacles after months at sea.Barnacles can often be seen clinging to the rocks along the shoreline.
- A metaphorical term used to describe a person or thing that is difficult to get rid of or detach from. nounHe was like a barnacle, always sticking around even when he wasn't wanted.The old regulations were barnacles on the new system, hindering its progress.