In Irish mythology Goibniu (Old Irish, pronounced ˈɡovʲnʲu) or Gaibhne (Modern Irish) was the smith of the Tuatha Dé Danann. He is believed to have been a smithing god and is also associated with hospitality.
The name of his father appears as Esarg or Tuirbe Trágmar, the 'thrower of axes'. Goibniu is often grouped together with Credne the silversmith and Luchta the carpenter as the Trí Dée Dána (three gods of art), who forged the weapons which the Tuath Dé used to battle the Fomorians. Alternatively, he is grouped with Credne and Dian Cecht the physician. When Nuada's arm is cut off in battle, Goibniu crafts him a new one of silver. He also makes weapons for the gods. In the Lebor Gabála Érenn, he is described as "not impotent in smelting", and is said to have died, along with Dian Cecht, of a "painful plague".
Goibniu also acts as a hospitaller who furnishes feasts for the gods. According to Altram Tige Dá Medar, the feast of Goibniu protected the Tuatha Dé from sickness and old age. He is said to be owner of the Glas Gaibhnenn, the magical cow of abundance. In the St Gall incantations, he is invoked against thorns, alongside Dian Cecht.
Goibniu may be the same figure as Culann.
His name can be compared with the Old Irish gobae ~ gobann ‘smith,’ Middle Welsh gof ~ gofein ‘smith,’ Gallic gobedbi ‘with the smiths,’ Latin faber ‘smith’ and with the Lithuanian gabija ‘sacred home fire’ and Lithuanian gabus ‘gifted, clever’.