imminency vs impendency

imminency and impendency both are nouns.

Word	Noun	Adjective	Verb	Adverb
imminency	Yes	No	No	No
impendency	Yes	No	No	No

As nouns, imminency and impendency are synonyms defined as:

imminency and impendency: the state of being imminent and liable to happen soon

Other synonyms of imminency include forthcomingness, imminence, imminentness, impendence.

imminency (noun)	impendency (noun)
the state of being imminent and liable to happen soon	the state of being imminent and liable to happen soon