horsemussel

Noun

horse mussel (plural horse mussels)

1. A northern horse mussel, any member of the species Modiolus modiolus of mussels of northern waters of Europe and the Atlantic and Pacific coasts of North America
2. (broadly) Any in subfamily Modiolinae of mussels.
3. Atrina squamifera, of South Africa
4. (New Zealand) Atrina zelandica, a large bivalve common from low tide to 45 m depth with a thin, dark, wedge-shaped shell covered with hollow spines.