I was in a SAT Prep class this year in my homeschool co-op, and every week my teacher would hand out vocabulary quizzes. On each one, there was a list of definitions and then a list of words to match them with. They were fun, and they really helped me in both expanding my personal vocabulary, and understanding words and their origins better. For instance, the word "somnolent", which was one of my words just today, means "sleepy or inducing sleep". I figured that word out because of the word part "som" or "somn". Since
"som" is in the word "insomnia" which means "inability to sleep", I figured out that the definition probably had to do with sleep, and I was right.
So the quizzes help with figuring out word roots and connecting them to other words, so that there's less chance you'll guess the meaning of a word and be wrong.
So this won't only help you in your writing, but it also ought to be fun.
Here are the rules:
1. No dictionaries allowed. You're on the honor code (and I may have minions watching you...)
2. I will post a word and the word type.
3. You will guess the meaning of the word.
4. You will post your guess.
5. The first person to guess right gets to pick the next word.
Sound fun? Good, jump right in!
The first word is:
Acerbic (adj.)
... 
A disease would be a noun. Acerbic is an adjective.
Your turn!