nisus vs striving

nisus and striving both are nouns.

Word	Noun	Adjective	Verb	Adverb
nisus	Yes	No	No	No
striving	Yes	No	No	No

As nouns, nisus and striving are synonyms defined as:

Other synonyms of nisus include pains, strain.

nisus (noun)	striving (noun)
an effortful attempt to attain a goal	an effortful attempt to attain a goal