actino-youdaoicibaDictYouDict[actino- 词源字典]
before vowels actin-, word-forming element meaning "pertaining to rays," from Greek aktis (genitive aktinos) "ray, radiance;" perhaps cognate with Sanskrit aktuh "light, ray," Gothic uhtwo "dawn, daybreak," Lithuanian anksti "early."[actino- etymology, actino- origin, 英语词源]