A Caribbean helmet shell of the genus Cassis, especially the king helmet (C. tuberosa) and the queen helmet (C. madagascariensis), both used in making shell cameos.
Origin
Mid 19th century; earliest use found in The Daily News.
Definition of black helmet in US English:
black helmet
noun
A Caribbean helmet shell of the genus Cassis, especially the king helmet (C. tuberosa) and the queen helmet (C. madagascariensis), both used in making shell cameos.
Origin
Mid 19th century; earliest use found in The Daily News.