sand dollar

noun

1. any of various flat, disklike sea urchins, as Mellita testudinata or Echinarachnius parma, that live on sandy bottoms off the coasts of the U.S.

sand dollar

noun

1. any of various flattened disclike echinoderms of the order Clypeasteroida, of shallow North American coastal waters: class Echinoidea (sea urchins)

Word History and Origins

Origin of sand dollar¹

An Americanism dating back to 1880–85