The root word "ject" , as in the word "injection", means what: to throw. The root word "graph", as in the word "autograph", means what: to write or draw. The root words "aud" and "audi", as in the word audio, mean what: to hear. The root words "vis" and "vid", as in the word "video" mean what? : to see. When the prefix "poly" is added to a word, it means what: many. The prefixes "en" and "em" mean what: to cause to be. "Pro" when added to the beginning of a word means what? : in favor of. When "Anti" is added to the beginning of a word, what does it mean: against. The prefix "sub" can be added to the front of a word to mean what: under. "ology" and "logy" can be added to a word to mean what: the study of