isomorphism vs isomorphy

isomorphism and isomorphy both are nouns.

Word	Noun	Adjective	Verb	Adverb
isomorphism	Yes	No	No	No
isomorphy	Yes	No	No	No

As nouns, isomorphism and isomorphy are synonyms defined as:

isomorphism and isomorphy: (biology) similarity or identity of form or shape or structure

isomorphism (noun)	isomorphy (noun)
(biology) similarity or identity of form or shape or structure	(biology) similarity or identity of form or shape or structure