Affixes

Some examples are theology, the study of the nature of God and religious belief; theocracy, a system of government in which priests rule in the name of God or a god; and theophany (Greek phainein, to show), a visible manifestation to humankind of God or a god.

The alkaloid called theobromine derives its name indirectly from the same source, as it occurs in seeds of the cocoa plant, whose genus is Theobroma (Greek brōma, food, hence ‘food of the gods’). However, theodolite, the surveying instrument, comes from another source, possibly the same root that is in words like theorem—Greek theōrein, to look at.