rigor rigor /ˈrɪgɝ/

noun

1. () Something hard to endure  ( asperity , grimness , rigorousness , hardship , rigor , rigour , rigourousness , severeness , severity )
   something hard to endure
    The asperity of northern winters
   the asperity of northern winters
   
2. [American] Excessive sternness  ( hardness , harshness , inclemency , rigor [American] , rigorousness , rigour [Canadian, British] , rigourousness [British, Non-standard] , severeness , severity , stiffness )
   excessive sternness
    Severity of character
   severity of character
    The harshness of his punishment was inhuman
   the harshness of his punishment was inhuman
    The rigors of boot camp
   the rigors of boot camp
   
3. [American] The quality of being valid and rigorous  ( cogency , rigor [American] , rigour [Canadian, British] , validity )
   the quality of being valid and rigorous
     The validity of the experiment's results was confirmed through multiple trials.
   The validity of the experiment's results was confirmed through multiple trials.