The Celtic goddess Epona is specifically identified by her horse symbolism. Her name is etymologically related to a Celtic word for horse (see below), and she is defined iconographically by the presence of one or more horses. The goddess is usually depicted either riding side-saddle on a mare or between two ponies or horses. Epigraphic dedications and images of Epona indicate her immense popularity within the Celtic world, being venerated particularly in the east of Gaul and the Rhineland, but known also as far north as Britain, and as far east as Bulgaria (Green M. Animals in Celtic Life and Myth. London/New York 1992. P. 204 – 207).
The name of the goddess derives from the Proto-Celtic *ekWo- ‘horse’ [Noun], Gaulish Epos – ‘Horse’ (Olr. ech, Ogam EQO-DDI, W: MW ebawl ‘foal’ [m] (GPC ebol) BRET: OBret. eb ‘horse’, ebol ‘foal’, MBret. ebeul [m] CO: OCo. ebol gl. Pullus CELTIB: Ekua-laku [PN] (A.63). Gaulish Equos - ’name of the ninth month’ (Coligny) may be an archaic form (with preserved qu < *kw). The Brit. forms (except OBret. eb) are from a derivative *ekwalo- (cf. also Celtib. ekualaku and ekualakos, which has been interpreted as a Nom. sg. of an adjective ‘belonging to ekuala’) (Matasovic R. Etymological Dictionary of Proto-Celtic. Leiden/Boston 2009). The element is common in Celtic names (for example Epacus, Epasius, Eppius, Eppia, Επηνοσ (Epenos), Epomeduos, Eporedorix, and the names of tribes, such as the Επίδιοι (Epidii) in Scotland, or in placenames such as Epomanduodurum in France (Delmarre pp. 163-164 and pp. 355-389), and Indo European cognates of Gaulish epo- are frequent in PN’s over a wide area (see S. Feist, Kultiir, Ausbreitung und Herkunft der Indogermanen (Berlin, 1913).
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