Pronunciation of Celtic

The various names used since classical times for the people known today as the Celts are of disparate origins.

The name Κελτοί Keltoi and Celtae is used in Greek and Latin, respectively, as the name of a people of the La Tène horizon in the region of the upper Rhine and Danube during the 6th to 1st centuries BC in Greco-Roman ethnography. The etymology of this name and that of the Gauls Γαλάται Galatai / Galli is of uncertain etymology. The name of the Welsh, on the other hand, is taken from the designator used by the Germanic peoples for Celtic- and Latin-speaking peoples, *Walhaz, meaning "foreign".

The linguistic sense of the name Celts, grouping all speakers of Celtic languages, is modern. In particular, aside from a 1st-century literary genealogy of Celtus the grandson of Bretannos by Heracles, there is no record of the term "Celt" being used prior to the 17th century in connection with the inhabitants of Ireland and Britain during the Iron Age.

The first recorded use of the name of Celts – as Κελτοί – to refer to an ethnic group was by Hecataeus of Miletus, the Greek geographer, in 517 BC, when writing about a people living near Massilia (modern Marseille). In the 5th century BC Herodotus referred to Keltoi living around the head of the Danube and also in the far west of Europe.

The etymology of the term Keltoi is unclear. Possible roots include Indo-European *k´el-‘to hide’ (also in Old Irish celid), IE *k´el- ‘to heat’ or *kel- ‘to impel’. Several authors have supposed it to be Celtic in origin, while others view it as a name coined by Greeks. Linguist Patrizia De Bernardo Stempel falls in the latter group, and suggests the meaning "the tall ones".

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