continuity vs coherency

continuity and coherency both are nouns.

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

As nouns, coherency is a hypernym of continuity; that is, coherency is a word with a broader meaning than continuity:

Other hypernyms of continuity include coherence, cohesion, cohesiveness.

continuity (noun)	coherency (noun)
the property of a continuous and connected period of time	logical and orderly and consistent relation of parts
a detailed script used in making a film in order to avoid discontinuities from shot to shot	the state of cohering or sticking together
uninterrupted connection or union