Lugos (Gaulish) or Lugus (Latin), also known by other names, is a god of the Celtic pantheon. His name is rarely directly attested in inscriptions, but his importance can be inferred from place names and ethnonyms and status as king of the gods. 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 him, and from the quasi-mythological narratives involving his later cognates, Welsh Lleu Llaw Gyffes and Irish Lugh Lámhfhada.

Lugh or Lug is a figure in Irish mythology. A member of the Tuatha Dé Danann, a group of supernatural beings, Lugh is portrayed as a warrior, a king, a master craftsman and a saviour. He is associated with skill and mastery in multiple disciplines, including the arts. Lugh also has associations with oaths, truth and the law, and therefore with rightful kingship. Lugh is linked with the harvest festival of Lughnasadh, which bears his name. His most common epithets are Lámfada and Samildánach. This has sometimes been anglicised as "Lewy of the Long Hand".