Acephala n. pl. (Zool.) That division of the Mollusca which includes the bivalve shells, like the clams and oysters; so called because they have no evident head. Formerly the group included the Tunicata, Brachiopoda, and sometimes the Bryozoa. See Mollusca.
Collaborative International Dictionary of English 0.48
Copyright © 2018 Free-Translator.com