existence

n. living, state of existing, state of being; life

The study of existence is a branch of philosophy known as ontology.Many questions arise concerning existence. Is what we experience and observe all there is to existence? Do abstract ideas, such as virtue, exist? Is existence orderly and knowable or chaotic and unknowable? Does there exist an external reality that is completely ontologically independent of our conceptual schemes, linguistic practices, and beliefs?
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Noun
1. the state or fact of existing; "a point of view gradually coming into being"; "laws in existence for centuries"
(synonym) being, beingness
(antonym) nonexistence, nonentity
(hypernym) state
(hyponym) actuality
(attribute) existent, existing
(derivation) exist, be
2. everything that exists anywhere; "they study the evolution of the universe"; "the biggest tree in existence"
(synonym) universe, creation, world, cosmos, macrocosm
(hypernym) natural object
(hyponym) closed universe
(member-meronym) galaxy, extragalactic nebula
(part-meronym) celestial body, heavenly body

n. existence, life, being, lifetime

(n.)
The state of existing or being; actual possession of being; continuance in being; as, the existence of body and of soul in union; the separate existence of the soul; immortal existence.
  

(n.)
That which exists; a being; a creature; an entity; as, living existences.
  

(n.)
Continued or repeated manifestation; occurrence, as of events of any kind; as, the existence of a calamity or of a state of war.