Ontology
Pronunciation : On*tol"o*gy
Part of Speech : n.
Etymology : [Gr. -logy: cf.F. ontologie.]
Definition : Defn: That department of the science of metaphysics which investigates and explains the nature and essential properties and relations of all beings, as such, or the principles and causes of being.
Source : Webster's Unabridged Dictionary, 1913