entity

American Heritage® Dictionary of the English Language, Fourth Edition

1. n. Something that exists as a particular and discrete unit: Persons and corporations are equivalent entities under the law.
2. n. The fact of existence; being.
3. n. The existence of something considered apart from its properties.

Century Dictionary and Cyclopedia

1. n. Being: in this, its original sense, the abstract noun corresponding to the concrete ens.
2. n. An independent ens; a thing; a substance; an ontological chimera. As a concrete noun, it is chiefly used to express the current notion of the mode of being attributed by scholastic metaphysicians to general natures and to formalities. Modern writers have generally said the schoolmen made entities of words, a judgment which seems to espouse the nominalistic side of the great dispute, although the writers who use this phrase are not decided nominalists. Such being the connection which by its associations gives the word entity its meaning, the latter is necessarily vague.
3. n. An individual fact or conception, having in itself all that is needed to constitute a characteristic whole.

Wiktionary

1. n. That which has a distinct existence as an individual unit. Often used for organisations which have no physical form.
2. n. An existent something that has the properties of being real, and having a real existence.
3. n. computing Anything about which information or data can be stored in a database; in particular, an organized array or set of individual elements or parts.
4. n. The state or quality of being or existence.

GNU Webster's 1913

1. n. A real being, whether in thought (as an ideal conception) or in fact; being; essence; existence.

WordNet 3.0

1. n. that which is perceived or known or inferred to have its own distinct existence (living or nonliving)