- acardiac[acardiac 词源字典]
- "Especially of one of a pair of monochorionic or conjoined twins: lacking a heart", Mid 19th cent.; earliest use found in Marshall Hall (1790–1857), physician and neurophysiologist. From Hellenistic Greek ἀκάρδιος without a heart + -ac, after acardia and cardiac.[acardiac etymology, acardiac origin, 英语词源]