Wikipedia
Mogons or Moguns was a god worshipped in Roman Britain and in Gaul. The main evidence is from altars dedicated to the god by Roman soldiers, but the deity is not a native Italic one. It appears to be Celtic. Inscriptional spellings include Mogetios, Mogounos, Mogti, Mounti, Mogont, Mogunt. Not all of these words are necessarily in the nominative case. For example, Mounti is a dative, probably *Mogunti, from a hypothetical nominative, *Moguns, of a back-formed Latin stem, *Mogunt-.
Etymologically the name can be seen to be the same as the English word Might personified. It has been translated by others as greatness or the great one. The fact that ordinary soldiers adopted him tends to support a "powerful" or "effective" interpretation rather than self-glorification.