the doctrine or belief that God is the universe and its phenomena (taken or conceived of as a whole) or the doctrine that regards the universe as a manifestation of God
(chemistry) any theory in which all matter is composed of tiny discrete finite indivisible indestructible particles; "the ancient Greek philosophers Democritus and Epicurus held atomic theories of the universe"
(psychology) a theory that reduces all mental phenomena to simple elements (sensations and feelings) that form complex ideas by association