elkyoudaoicibaDictYouDict[elk 词源字典]
elk: [OE] The Indo-European base *ol-, *elproduced a number of names for deerlike animals – Greek élaphos ‘stag’, for example, and Welsh elain ‘hind’, not to mention English eland. In its Germanic descendants, two main lines of development are evident: its extensions *olk- and *elk- produced respectively Germanic *algiz (whence Old Norse elgr) and Germanic *elkho(n)- (whence Old English colh).

It is not actually entirely clear which of these two is represented by modern English elk, which is first unequivocally recorded in the late 15th century. It is formally possible that it could be a survival of the Old English word, with its final /kh/ sound changed to /k/, but the long gap in the written record between Old English eolh and Middle English elk suggests that it could be an Old Norse borrowing.
=> eland[elk etymology, elk origin, 英语词源]
elk (n.)youdaoicibaDictYouDict
late Old English elch, from Old Norse elgr or from an alteration of Old English elh, eolh (perhaps via French scribes), or possibly from Middle High German elch (OED's suggestion), all from Proto-Germanic *elkh- (source also of Old High German elaho). The modern word "is not the normal phonetic representative" of the Old English one [OED].

The Germanic words are related to the general word for "deer" in Balto-Slavic (such as Russian losu, Czech los; also see eland), from PIE *olki-, perhaps with reference to the reddish color from root *el- (2) "red, brown" (in animal and tree names); compare Sanskrit harina- "deer," from hari- "reddish-brown." Greek alke and Latin alces probably are Germanic loan-words. Applied to similar-looking but unrelated animals in North America. Benevolent and Protective Order of Elks founded N.Y.C. 1868, originally a society of actors and writers.