What does "elk" mean?

Elk: A large deer, of several species. The European elk (Alces machlis or Cervus alces) is closely allied to the American moose. The American elk, or wapiti (Cervus Canadensis), is closely related to the European stag. See Moose, and Wapiti. Irish elk (Paleon.), a large, extinct, Quaternary deer (Cervus giganteus) with widely spreading antlers. Its remains have been found beneath the peat of swamps in Ireland and England. See Illustration in Appendix; also Illustration of Antler. -- Cape elk (Zoöl.), the eland.