proportionality vs proportional

proportionality and proportional both are nouns.

Word	Noun	Adjective	Verb	Adverb
proportionality	Yes	No	No	No
proportional	Yes	Yes	No	No

proportionality (noun)	proportional (noun)
harmonious arrangement or relation of parts or elements within a whole (as in a design)	one of the quantities in a mathematical proportion
a ratio of two quantities that is constant

proportionality (adjective)	proportional (adjective)
	properly related in size or degree or other measurable characteristics; usually followed by `to'
	having a constant ratio