Theos

Theos, written in Greek as θεός and commonly romanized as theos, is a noun meaning god. In ancient Greek religion and philosophy it referred to a deity or deities in general; the plural form is theoi. In various religious contexts, theos could denote a specific god within a pantheon or, in monotheistic usage, the supreme deity of the God of Israel or the Christian God. In modern Greek, Θεός (Theós) is the standard word for God.

Theos is the linguistic source of many English terms through the prefix theo- and related roots. Theos appears in words such as theology (the study of God), theism (belief in a god or gods), atheism (belief that there is no god), polytheism and monotheism (belief in multiple or a single god), theophany (a visible appearance of a deity to a person), theocracy (government viewed as or run by divine authority), and theogony (the birth or origin of the gods). In classical literature, theos is used to refer to individual gods within the Greek pantheon as well as to discuss divine activity in the world.

Beyond linguistic usage, the term also appears as a proper noun in certain contexts. The Theosophical Society, founded in 1875, uses the term theos to signal its focus on theosophical philosophy—a blend of religion, philosophy, and occult ideas—though this organization is distinct from mainstream theology. Overall, theos plays a central role in religious language, philosophy of religion, and the vocabulary of Western thought.