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.
Start with the suffix at the end of the term. The suffix -GRAM means a record. Now look at the beginning of the term. ELECTR is a word root, and it means. electricity. This medical term has two roots. The second root is CARDI, meaning heart. Whenever you see CARDI in other medical terms, you will know that it means heart. -LOGY, which means study of. Next, look at the beginning of the term.