(philosophy, uncountable) The branch of philosophy which studies fundamental principles intended to describe or explain all that is, and which are not themselves explained by anything more fundamental; the study of first principles; the study of being insofar as it is being (ens in quantum ens).
Philosophers sometimes say that Metaphysics is the study of the ultimate nature of the universe.
(philosophy, countable) The view or theory of a particular philosopher or school of thinkers concerning the first principles which describe or explain all that is.
The Metaphysics of Thomas Aquinas holds that all real beings have both essence and existence.
In Aristotelian Metaphysics physical objects have both form and matter.
In his Pensées, Pascal mentioned some first principles recognized within his metaphysics: space, time, motion, and number.
(uncountable, by extension from the philosophical sense) Any fundamental principles or rules.
(uncountable) The study of a supersensual realm or of phenomena which transcend the physical world.
I have a collection of books on metaphysics, covering astral projection, reincarnation, and communication with spirits.
(uncountable) Displeasingly abstruse, complex material on any subject.
This political polemic strikes me as a protracted piece of overwrought, fog shrouded metaphysics!
(countable) Plural of countable senses of metaphysic.