ascendancy vs ascendency

ascendancy and ascendency both are nouns.

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

As nouns, ascendancy and ascendency are synonyms defined as:

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

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

ascendancy (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