ascendency vs dominance

ascendency and dominance both are nouns.

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

As nouns, ascendency and dominance are synonyms defined as:

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

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

ascendency (noun)	dominance (noun)
the state that exists when one person or group has power over another	the power or right to give orders or make decisions
	superior development of one side of the body
	the organic phenomenon in which one of a pair of alleles present in a genotype is expressed in the phenotype and the other allele of the pair is not
	the state that exists when one person or group has power over another