What is the relationship between a strong vocabulary and good communication skills?

Most jobs require someone with good communication skills. Can one have excellent communication skills with an average vocabulary?What is the relationship between a strong vocabulary and good communication skills?
I would argue that it is easier to have good communication skills with an average vocabulary. If you don't know how to talk loquaciously (or with big words), it is harder to talk above others (who may feel you are just trying to make them feel less intelligent than you). What is more important than knowing big words is knowing how to use the "small" words that you do know properly. Learn proper grammar, and you will do much better with communication. Also, learning how to speak (using body language, speaking loudly enough for all that you want to hear to hear what you are saying, proper posture) will go a long way toward making you look intelligent without making you look arrogant (which is the biggest problem facing those who know words like loquacious).



If you still feel you would prefer using "big" words, make sure you know how to use them properly. No one wants to look like Mike Tyson after his prison stint, in which he had learned how to say the words but not their meaning. "I don't know if I'm estatic or ludicrous," sounds rather foolish, don't you think. Stick with what you know, but make sure you know it and you'll do very well (not good) as a speaker.