Emily Dickinson Lexicon

THE'UR-GY, n. [Gr. θεουργια; Θεος, God, and εργον, work.]

The art of doing things which it is the peculiar province of God to do; or the power or act of performing supernatural things by invoking the names of God or of subordinate agents; magic. This has been divided by some writers into three parts; theurgy, or the operation by divine or celestial means; natural magic, performed by the powers of nature; and necromancy, which proceeds by invoking demons. Cyc.