Lugus

Lugus was a deity of the Celtic pantheon. His name is rarely directly attested in inscriptions, but his importance can be inferred from place names and ethnonyms, and his nature and attributes are deduced from the distinctive iconography of Gallo-Roman inscriptions to Mercury, who is widely believed to have been identified with Lugus, and from the quasi-mythological narratives involving his later cognates, Welsh Lleu Llaw Gyffes (Lleu of the Skillful Hand) and Irish Lugh Lámhfhada (Lugh of the Long Arm).

The exact etymology of Lugus is unknown and contested. The Proto-Celtic root of the name, *lug-, is generally believed to have been derived from one of several different Proto-Indo-European roots, such as *leug- "black",*leuǵ- "to break", and *leugʰ- "to swear an oath", It was once thought that the root may be derived from Proto-Indo-European *leuk- "to shine", but there are difficulties with this etymology and few modern scholars accept it as being possible (notably because Proto-Indo-European *-k- never produced Proto-Celtic *-g-).

The god Lugus is mentioned in a Celtiberian inscription from Peñalba de Villastar in Spain, which reads:

The exact interpretation of the inscription is debated, but the phrase "to Luguei" (where the theonym appears in the dative singular following the preposition to "to, for", thus "to/for Lugus") clearly indicates a dedication to the god Lugus.

Additionally, the name is attested several times in the plural, for example: nominative plural Lugoues in a single-word (and potentially Gaulish) inscription from Avenches, Switzerland, and dative plural in a well known Latin inscription from Uxama (Osma), Spain:

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