Medical Terminology Section I Introduction to … Health (2 days ago) When breaking words down, define: a.The end of the word 1st (suffix) b. The beginning of the word 2nd (prefix or word root) c. The middle of the 3rd (word root or roots) 2.Use a medical dictionary to look words up to check the meanings if you are not completely sure. 3. Medical dictionaries will also help you learn how to ....