Chairness

There was, according to him [an artificial monster created by a Swedish scientist], a 'goodness' that made things good, an 'evil principle' that made them bad, [...] and a 'chairness' or 'boxness' that made things chairs and boxes.

Source: wiktionary

Similarly when we call triangularity or chairness an idea or notion or concept, we do not mean to deny that these natures are really manifested in particulars; we are only saying that their reality, like that of the particulars, presupposes a thinking subject.

Source: wiktionary

He extended his finger and outlined the shape of the chair. "It's about forms and negative space—she's taken the chairness away from the chair and left it purely object."

Source: wiktionary

I can identify the pattern of wood grain on my chair at Mom and Dad's kitchen table, but I don't try to sketch it in my mind. For me, chairness is nonvisual; it's the feel of a seat connected to four legs and a backrest.

Source: wiktionary