Apparently, there's evidence suggesting that to "own" a new word, you have to say it out loud at least 18 times. The vocalization, along with the repetition, apparently help to reinforce memories in the various language areas in your brain. Which means that you can recall and use the terms easily.
I know that seems silly . . . even childish. But think about it. Silly as it may seem, isn't it worth reducing your study time and improving your knowledge quickly?
Adapted from a post at The A&P Student