Word Study
acephala
CIDE DICTIONARY
acephala, n. pl. [NL., fr. Gr. , adj. neut. pl., headless. See Acephal.].
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. [1913 Webster]
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