Megaloceros (from Greek: μεγαλος megalos + κερας keras, literally "Great Horn"; see also Lister (1987)) is an extinct genus of deer whose members lived throughout Eurasia from the Pleistocene to the early Holocene. The type and only undisputed member of the genus, Megaloceros giganteus, vernacularly known as the "Irish elk" or "giant deer", is also the best known. Fallow deer are thought to be their closest living relatives. Megaloceros has been suggested to be closely related to other genera of "giant deer", like the East Asian genus Sinomegaceros and the largely European Praemegaceros, the species of both genera having been historically attributed to Megaloceros.