Translation

実在性 / 現存在 / 「あれ」であること

Meaning

The quality or state of being a particular thing, specifically the fact of its existence rather than its nature or attributes.

Examples

• The philosopher argued that we must distinguish between the whatness of an object and its raw thatness.
  The philosopher argued that we must distinguish between the whatness of an object and its raw thatness.
• He was fascinated by the sheer thatness of the mountain, which seemed to exist independently of any human perception.
  He was fascinated by the sheer thatness of the mountain, which seemed to exist independently of any human perception.