The ancient Greek word means “craftsman” or “artisan.” Plato, in the Timaeus, uses the word for the maker of the universe. Plato says of this maker that he is unreservedly good and so desired that the world should be as good as possible. The reason why the world is not better than it is is that the demiurge had to work on pre-existing chaotic matter. Thus, the demiurge is not an omnipotent creator.
Early Christian philosophers were quick to claim that the demiurge represented pagan philosophy’s anticipation of the God of revealed religion.
(Lloyd P. Gerson, The Oxford Companion to Philosophy, 183)