ascendance vs ascendency

ascendance and ascendency both are nouns.

Word	Noun	Adjective	Verb	Adverb
ascendance	Yes	No	No	No
ascendency	Yes	No	No	No

As nouns, ascendance and ascendency are synonyms defined as:

ascendance and ascendency: the state that exists when one person or group has power over another

Other synonyms of ascendance include ascendancy, ascendence, control, dominance.

ascendance (noun)	ascendency (noun)
the state that exists when one person or group has power over another	the state that exists when one person or group has power over another