In Celtic mythology, Teutates is a Gallic theonym known only from the epic La Pharsale by Lucain, an account of the civil war between Julius Caesar and Pompey; he is mentioned with Esus and Taranis. It is an archaic form or variant of Toutatis, it comes from teutã which evolved into touta and totã. The meaning is "father of the tribe, of the nation", it is the protective god of a community and its territory, with a warlike connotation. It is the same notion that we find in the Irish Celtic mythology of tuath (the tribe), with the Tuatha Dé Danann. Teutates can be brought closer to Dagda and compared to the Roman Mars. But given the weakness of the sources, it is hardly possible to say more.
Celtologist Joseph Vendryes has speculated that it could be an adjective, used to avoid pronouncing the name of the god, in accordance with the respect of a taboo. This god is not necessarily the same from one tribe to another.