In Lusitanian and Celtic polytheism, Borvo (also known variously as Bormo, Bormanus, Bormanicus, Borbanus, Boruoboendua, Vabusoa, Labbonus or Borus) was the Celtic God of Minerals and healing deity associated with bubbling spring water.
In Gaul, he was particularly worshipped at Bourbonne-les-Bains, in the territory of the Lingones, where ten inscriptions are recorded. Two other inscriptions are recorded, one (CIL 13, 02901) from Entrains-sur-Nohain and the other (CIL 12, 02443) from Aix-en-Savoie in Gallia Narbonensis. Votive tablets inscribed ‘Borvo’ show that the offerers desired healing for themselves or others. Many of the sites where offerings to Borvo have been found are in Gaul: inscriptions to him have been found in Drôme at Aix-en-Diois, Bouches-du-Rhône at Aix-en-Provence, Gers at Auch, Allier at Bourbon-l'Archambault, Savoie at Aix-les-Bains, Saône-et-Loire at Bourbon-Lancy, in Savoie at Aix-les-Bains, Haute-Marne at Bourbonne-les-Bains and in Nièvre at Entrains-sur-Nohain. However, findings have also been uncovered in the Netherlands at Utrecht, where he is called Boruoboendua Vabusoa Labbonus, and in Portugal at Caldas de Vizella and at Idanha a Velha, where he is called Borus and identified with Mars. At Aix-en-Provence, he was referred to as Borbanus and Bormanus but at Caldas de Vizella in Portugal, he was hailed as Bormanicus, and at Burtscheid and at Worms in Germany as Borbetomagus.
In all of his centers of worship where he was assimilated to a Roman god, Borvo was equated with Apollo. Many local gods were identified with Apollo in his capacity of god of healing. He bore similarities to the goddess Sirona, who was also a healing deity associated with mineral springs, but he is clearly distinct from her. Variant forms of his name include Bormo and Bormanus (in Gaul) and Bormanicus (in Portugal). The names Bormanus, Bormo and Borvo are found on inscriptions as names of river or fountain gods.
Borvo was frequently associated with a divine consort. Eight of the inscriptions mention the goddess Damona. Here is an example of one of them (CIL 13, 05911):
In other areas, Borvo's partner is the goddess Bormana. Bormana was, in some areas, worshipped independently of her male counterpart. Gods like Borvo, and others, equated with Apollo, presided over healing springs, and they are usually associated with goddesses, as their husbands or sons. He is found in Drôme at Aix-en-Diois with Bormana and in Saône-et-Loire at Bourbon-Lancy and in Haute-Marne at Bourbonne-les-Bains with Damona but he is accompanied by the ‘candid spirit’ Candidus in Nièvre at Entrains-sur-Nohain. In the Netherlands at Utrecht as Boruoboendua Vabusoa Lobbonus, he is found in the company of an Celtic Hercules, Macusanus and Baldruus.
The variants Borus ~ Borvo ~ Bormo ~ Bormanus seem to be based on a root *boru-. This root in turn is thought to be a variant of the Proto-Celtic root *beru- ‘boil’ and may have meant ‘to bubble.’ Cognate with the names is the Welsh berw ‘boiling.’ and the Goidelic bruich, ‘boil, cook’. The words are variants of a Proto-Indo-European base *bhreue- ‘to bubble, boil, effervesce’ (cf. Skt. Bhurnih ‘violent, passionate,’ Gk. Phrear ‘well, spring,’ L. fervere ‘to boil, foam,’ Thracian Gk. Brytos ‘fermented liquor made from barley;’ O.E. beorma ‘yeast;’ O.H.G. brato ‘roast meat’ ) from which the English word brew also derives. The Proto-Celtic forms of the name variants most probably were *Boru-s, *Borwon-, *Borumāno-s and *Borumān-iko-s and the names most probably meant the ‘Bubbler.’ The base of these names is furthermore the source of the name of the River Barrow. In Irish, the river is called Bearú, the ‘Boiling, Bubbling’ and in Irish mythology it was Dian Cecht, a great healer of the Tuatha Dé Danann, who first caused the river to ‘boil’. *Borvo- is the stem Macbain reconstructs for the Irish borbhan, ‘a purling sound,’ and which he also relates to the Welsh berw, ‘seethe,’ French Bourbon and the Latin fervo, ‘boil’.