coherency vs cohesion

coherency and cohesion both are nouns.

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

As nouns, coherency and cohesion are synonyms defined as:

Other synonyms of coherency include coherence, cohesiveness.

coherency (noun)	cohesion (noun)
logical and orderly and consistent relation of parts	(physics) the intermolecular force that holds together the molecules in a solid or liquid
the state of cohering or sticking together	(botany) the process in some plants of parts growing together that are usually separate (such as petals)
	(linguistics) the grammatical and lexical linking within a text or sentence that holds a text together and gives it meaning.
	the state of cohering or sticking together