acoel
演变路径（由近及远）
- 英语
- 源自 ←古希腊语 ἄκοιλος “not hollow”
词源说明
From group name Acoela, from Ancient Greek ἄκοιλος (ákoilos, “not hollow”).
释义（英文）
名词 Noun
- (zoology) Any of the order Acoela of xenacoelomorphs that resemble flatworms and were originally classified as such.
- (zoology, obsolete) A member of the order Acoela of marine flatworms, which lack a digestive cavity with definite walls. [from 20th c.]