Acmaea testudinalis

Limpet Lim"pet (l[i^]m"p[e^]t), n. [Prob. through French fr. L. lepas, -adis, Gr. lepa`s, -a`dos.] (Zo["o]l.) 1. In a general sense, any hatshaped, or conical, gastropod shell. [1913 Webster]

2. Any one of many species of marine shellfish of the order {Docoglossa}, mostly found adhering to rocks, between tides. [1913 Webster]

Note: The common European limpets of the genus {Patella} (esp. {Patella vulgata}) are extensively used as food. The common New England species is {Acm[ae]a testudinalis}. Numerous species of limpets occur on the Pacific coast of America, some of them of large size. [1913 Webster]

3. Hence: Somthing or someone that clings tenaciously to another object or person; specifically a military explosive device having magnets allowing it to cling to a metallic target object, such as the hull of a ship. [PJC]

3. Any species of {Siphonaria}, a genus of limpet-shaped Pulmonifera, living between tides, on rocks. [1913 Webster]

4. A keyhole limpet. See {Fissurella}. [1913 Webster]