noun
ZoologyA member of the group Acoela of simple flatworms that have no distinct gut.
adjective
ZoologyOf or relating to the group Acoela.
Origin
1930s; earliest use found in The Biological Bulletin. From scientific Latin Acoela (W. N. Uljanin 1870) from ancient Greek ἄκοιλος not hollow from ἀ- + κοῖλος hollow; compare ancient Greek ἀκοίλιος without ducts, without stomach.
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