If you are rigorous when you do something, you do it extremely carefully and precisely. A rigorous inspection of your tax records has revealed the government owes you money. Congratulations!

The Latin root for rigorous is rigor, meaning “stiffness.” This might remind you of rigor mortis, the stiffening of a body after death, as often seen on cop shows. This is a good, if creepy, way of remembering the meaning of rigorous: rigorous people are stiff and unbending about the standards of their work. This requires being alive, of course.

Definitions of rigorous

adj rigidly accurate; allowing no deviation from a standard

rigorous application of the law”
marked by strict and particular and complete accordance with fact

adj demanding strict attention to rules and procedures

rigorous discipline”
stringent, tight
requiring more than usually expected or thought due; especially great patience and effort and skill

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