Thisness

Part of speech: noun

Definitions

1. The property that captures the distinct essence of an individual entity A unique characteristic that identifies a particular object or concept The quality that embodies the individuality and recognizable attributes of a specific thing or idea
2. The inherent quality that makes an entity distinct from all others and defines its individuality
3. A characteristic inherent to an object or concept that marks its unique existence apart from others

Etymology: "Thisness" is formed from the English pronoun "this" with the suffix "-ness," which turns an adjective or pronoun into a noun for a quality or state. The result names the quality of being this particular thing rather than any other. The concept itself is older than the English word. Medieval scholastic philosophers, following Aristotle's concern with what makes an individual thing the one it is, used a Latin term "haecceitas," built on "haec," the feminine form of "hic" ("this"), with the same suffix sense. "Thisness" is essentially the English counterpart of that scholastic coinage, carrying the same idea into the vernacular.