rheumatic vs rheumy

rheumatic is a noun but rheumy is not a noun.

Word	Noun	Adjective	Verb	Adverb
rheumatic	Yes	Yes	No	No
rheumy	No	Yes	No	No

As adjectives, rheumatic and rheumy are synonyms defined as:

Other synonyms of rheumatic include arthritic, creaky, rheumatoid.

rheumatic (noun)	rheumy (noun)
a person suffering with rheumatism

rheumatic (adjective)	rheumy (adjective)
of or pertaining to arthritis	of or pertaining to arthritis
	moist, damp, wet (especially of air)