A god is a deity, a heavenly being that is worshipped.
We know there are many gods, but to us there is only one God.
1Corinthians 8:5-6 Indeed, even though there are so-called gods in heaven and on earth (there are, to be sure, many "gods" and many "lords"), yet for us there is one God, the Father, from whom all things are and for whom we exist, and one Lord, Jesus Christ, through whom all things are and through whom we exist.