Meaning of crown shell in English:

crown shell

noun

rare
  • Any of various marine shells thought to resemble a crown (frequently with distinguishing word indicating the origin of the shell or the shape of the crown); (in later use) specifically the shell of any whelk or conch of the genus Melongena, found off the coasts of tropical America.

Origin

Mid 18th century; earliest use found in Robert Dodsley (1704–1764), bookseller and writer.