coherence vs coherency

coherence and coherency both are nouns.

Word	Noun	Adjective	Verb	Adverb
coherence	Yes	No	No	No
coherency	Yes	No	No	No

As nouns, coherence and coherency are synonyms defined as:

coherence and coherency: logical and orderly and consistent relation of parts

As nouns, coherence and coherency are synonyms defined as:

Other synonyms of coherence include cohesion, cohesiveness.

coherence (noun)	coherency (noun)
logical and orderly and consistent relation of parts	logical and orderly and consistent relation of parts
the state of cohering or sticking together	the state of cohering or sticking together