strictness vs stringency

strictness and stringency both are nouns.

Word	Noun	Adjective	Verb	Adverb
strictness	Yes	No	No	No
stringency	Yes	No	No	No

As nouns, strictness and stringency are synonyms defined as:

strictness (noun)	stringency (noun)
uncompromising resolution	conscientious attention to rules and details
conscientious attention to rules and details	a state occasioned by scarcity of money and a shortage of credit