'overgod' originates from Modern English, specifically formed from the elements 'over' and 'god'; 'over' ultimately derives from Old English 'ofer' where 'ofer' meant 'above', and 'god' comes from Old English 'god' meaning 'deity'.

'overgod' developed as a transparent compound of 'over' + 'god' in Modern English usage, modeled on compounds that place one element above or over another; it has appeared in theological and literary texts to denote a god above other gods and later in fictional contexts.

Initially, the components literally conveyed 'a god above (other gods)', and the term has largely retained this core sense of a supreme or overarching deity, though its use is relatively rare and often stylistically marked (theological or fictional).