Alaunus

Alaunus or Alaunius was a Gaulish god of healing and prophecy. His name is known from inscriptions found in Lurs, Alpes-de-Haute-Provence in southern France and in Mannheim in western Germany. In the latter inscription, Alaunus is used as an epithet of Mercury. The name of this deity is also found as a placename both of sites and rivers. Its feminine form Alauna appears in the Roman-era names of Valognes in Normandy, Maryport and Watercrook in Cumbria, Alcester in Warwickshire, Ardoch in Perthshire, and Learchild and the River Aln in Northumberland.

The etymology of the name remains uncertain. Some connect it with the Proto-Celtic root reconstructed as *alo- ("feed, raise, nurture"), but Matasović discounts it.Nicolaisen connected the various hydronyms to the unrelated Proto-Indo-European root reconstructed as *el- or *ol- meaning "to flow or stream". Monaghan posits an unrelated Celtic river goddess Alauna, found in Brittany.

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