rectangularity vs oblongness

rectangularity and oblongness both are nouns.

Word	Noun	Adjective	Verb	Adverb
rectangularity	Yes	No	No	No
oblongness	Yes	No	No	No

As nouns, rectangularity and oblongness are synonyms defined as:

rectangularity and oblongness: the property of being shaped like a rectangle

rectangularity (noun)	oblongness (noun)
the property of being shaped like a rectangle	the property of being shaped like a rectangle