pentadactylyoudaoicibaDictYouDict[pentadactyl 词源字典]
"(Of a vertebrate limb) having five toes or fingers, or derived from such a form, as characteristic of all tetrapods", Early 19th century: from penta- 'five' + Greek daktulos 'finger'.[pentadactyl etymology, pentadactyl origin, 英语词源]