From Longman Dictionary of Contemporary Englishrigourrig‧our British English, rigor American English /ˈrɪɡə $ -ər/ noun 1 → the rigours of something2 EXACT[uncountable] great care and thoroughness in making sure that something is correct Their research seems to me to be lacking in rigour.
Examples from the Corpus
rigour• Regretfully I see in him a nature inclined to harshness and rigour, with little tenderness and forthrightness.• With even greater environmental rigour, harshness itself is a major direct cause of community structure.• The facade of the building at least escaped from rigour.• A lack of rigour in the investigation.• This limits the potential rigour of design because the anchor of skill training is the specification of the objectives.• Ferguson has restored the rigour of self-scrutiny to history.• The difficulty with many bibliometric studies is their lack of theoretical rigour, as Gilbert and Woolgar have pointed out. 