Rigor is something strict, severe or demanding. 1  Harsh and strict treatment in the military for cadets is an example of rigor. 2  Freezing weather and ice are examples of the rigors of winter.  Difficult and challenging academic courses are an example of academic rigor.
The suffix gram means to draw or write. This is used in telegram.
1 Gram. 2  denoting the voice or form of a verb whose subject is the recipient (object) of the action of the verb: opposed to active. 3  in or of the passive voice: in âThe tree was struck by lightning,â was struck is a passive construction. Finance of or relating to an investor not involved actively in management, policymaking, etc.: passive losses. 2  Gram. 3  denoting the voice or form of a verb whose subject is the recipient (object) of the action of the verb: opposed to active.