immortal (adj.)youdaoicibaDictYouDict[immortal 词源字典]
"deathless," late 14c., from Latin immortalis "deathless, undying," from assimilated form of in- "not, opposite of" (see in- (1)) + mortalis "mortal" (see mortal (adj.)). In reference to fame, literature, etc., attested from 1510s (a sense also found in classical Latin). As a noun, from mid-17c.[immortal etymology, immortal origin, 英语词源]