Maponos

In ancient Celtic religion, Maponos or Maponus ("Great Son") is a god of youth known mainly in northern Britain but also in Gaul. In Roman Britain, he was equated with Apollo.

The Welsh mythological figure Mabon ap Modron is apparently derived from Maponos, who by analogy we may suggest was the son of the mother-goddess Dea Matrona. The Irish god Aengus, also known as the Mac Óg ("young son"), is probably related to Maponos, as are the Arthurian characters Mabuz and Mabonagrain.

In Gaulish, mapos means a young boy or a son. The suffix -onos is augmentative. Besides the theonym Maponos, the root mapos is found in personal names such as Mapodia, Mapillus, and Maponius; mapo is also found in the Carjac inscription (RIG L-86). The root is Proto-Indo-European

In Insular Celtic languages, the same root is found in Welsh, Cornish and Breton mab meaning son (Delamarre 2003 pp. 216–217), derived from Common Brythonic *mapos (identical to Gaulish). In Old Irish, macc also means son; it is found in Ogham inscriptions as the genitive maqui, maqqi, maqui (Sims-Williams 2003 pp. 430–431) with a geminative expressive doubling

He therefore personified youthfulness, which would explain the syncretism with the Graeco-Roman god Apollo.

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