residency vs residence

residency and residence both are nouns.

Word	Noun	Adjective	Verb	Adverb
residency	Yes	No	No	No
residence	Yes	No	No	No

As nouns, residency and residence are synonyms defined as:

Other synonyms of residency include abidance.

residency (noun)	residence (noun)
the act of dwelling in a place	the act of dwelling in a place
the position of physician who is receiving special training in a hospital (usually after completing an internship)	the official house or establishment of an important person (as a sovereign or president)
	a large and imposing house
	any address at which you dwell more than temporarily