nisus
noun
ni·sus ˈnī-səs 
plural nisus ˈnī-səs
-ˌsüs
: a mental or physical effort to attain an end : a perfective urge or endeavor
Word History
Etymology
Latin, from niti to lean, rely, strive; akin to Latin nictare to wink — more at connive
First Known Use
1699, in the meaning defined above
Medical Definition
nisus
noun
ni·sus ˈnī-səs
plural nisus -səs, -ˌsüs
: a mental or physical effort to attain an end