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. (April 2018)
The Proto-Germanic meaning of *ǥuđán and its etymology is uncertain. It is generally agreed that it derives from a Proto-Indo-European neuter passive perfect participle *ǵʰu-tó-m. This is similar to Persian word for God, Khudan. This form within (late) Proto-Indo-European itself was possibly ambiguous, and thought to derive from a root *ǵʰeu̯- "to pour, libate" (Sanskrit huta, see hotṛ), or from a root *ǵʰau̯- (*ǵʰeu̯h2-) "to call, to invoke" (Sanskrit hūta). Sanskrit hutá = "having been sacrificed", from the verb root hu = "sacrifice", but a slight shift in translation gives the meaning "one to whom sacrifices are made."
Depending on which possibility is preferred, the pre-Christian meaning of the Germanic term may either have been (in the "pouring" case) "libation" or "that which is libated upon, idol" — or, as Watkins opines in the light of Greek χυτη γαια "poured earth" meaning "tumulus", "the Germanic form may have referred in the first instance to the spirit immanent in a burial mound" — or (in the "invoke" case) "invocation, prayer" (compare the meanings of Sanskrit brahman) or "that which is invoked".
A significant number of scholars have connected this root with the names of three related Germanic tribes: the Geats, the Goths and the Gutar. These names may be derived from an eponymous chieftain Gaut, who was subsequently deified. He also sometimes appears in early Medieval sagas as a name of Odin or one of his descendants, a former king of the Geats (Gaut(i)), an ancestor of the Gutar (Guti), of the Goths (Gothus) and of the royal line of Wessex (Geats) and as a previous hero of the Goths (Gapt).
Some variant forms of the name Odin such as the Lombardic Godan may point in the direction that the Lombardic form actually comes from Proto-Germanic *ǥuđánaz. Wōdanaz or Wōđinaz is the reconstructed Proto-Germanic name of a god of Germanic paganism, known as Odin in Norse mythology, Wōden in Old English, Wodan or Wotan in Old High German and Godan in the Lombardic language. Godan was shortened to God over time and was adopted/retained by the Germanic peoples of the British isles as the name of their deity, in lieu of the Latin word Deus used by the Latin speaking Christian church, after conversion to Christianity.
During the complex christianization of the Germanic tribes of Europe, there were many linguistic influences upon the Christian missionaries. One example post downfall of the western Roman Empire are the missionaries from Rome led by Augustine of Canterbury. Augustine's mission to the Saxons in southern Britain was conducted at a time when the city of Rome was a part of a Lombardic kingdom. The translated Bibles which they brought on their mission were greatly influenced by the Germanic tribes they were in contact with, chief among them being the Lombards and Franks. The translation for the word deus of the Latin Bible was influenced by the then current usage by the tribes for their highest deity, namely Wodan by Angles, Saxons, and Franks of north-central and western Europe, and Godan by the Lombards of south-central Europe around Rome. There are many instances where the name Godan and Wodan are contracted to God and Wod. One instance is the wild hunt (a.k.a. Wodan's wild hunt) where Wod is used.
The earliest uses of the word God in Germanic writing is often cited to be in the Gothic Bible or Wulfila Bible, which is the Christian Bible as translated by Ulfilas into the Gothic language spoken by the Eastern Germanic, or Gothic, tribes. The oldest parts of the Gothic Bible, contained in the Codex Argenteus, is estimated to be from the fourth century. During the fourth century, the Goths were converted to Christianity, largely through the efforts of Bishop Ulfilas, who translated the Bible into the Gothic language in Nicopolis ad Istrum in today's northern Bulgaria. The words guda and guþ were used for God in the Gothic Bible.
In 19th-century scholarship, there were a number of alternative etymologies suggested. Morgan Kavanagh in The Origin of Language and Myths claimed that the word god was taken from the Buddha's patriarchal name of Gotama. Henry Scadding, and Henry Le Mesurier in his book Mer-cur-ius, or The Word Maker, also connected Lombard Guodan to Gotama Buddha. The connection of Gwydion with Wotan (but not with god) is due to Jacob Grimm.