Ontology as a branch of philosophy is the science of what is, of the kinds and
structures of objects, properties, events, processes and relations in every area of
reality. ‘Ontology’ is often used by philosophers as a synonym for ‘metaphysics’
(literally: ‘what comes after the Physics’), a term which was used by early students of
Aristotle to refer to what Aristotle himself called ‘first philosophy’. The term ‘ontology’ (or ontologia) was itself coined in 1613, independently, by two
philosophers, Rudolf Göckel (Goclenius), in his Lexicon philosophicum and Jacob
Lorhard (Lorhardus), in his Theatrum philosophicum. The first occurrence in English
recorded by the OED appears in Bailey’s dictionary of 1721, which defines ontology
as ‘an Account of being in the Abstract’
