rigor

nouns

something hard to endure
"the asperity of northern winters"
asperity, grimness, hardship, rigor, rigorousness, rigour, rigourousness, severeness, severity
the quality of being valid and rigorous
cogency, rigor, rigour, validity
is derived from
rigorous
excessive sternness
"severity of character"; "the harshness of his punishment was inhuman"; "the rigors of boot camp"
hardness, harshness, inclemency, rigor, rigorousness, rigour, rigourousness, severeness, severity, stiffness
is derived from
rigorous