Contemptible and contemptuous

Many people confuse the words contemptible and contemptuous. Contemptible means despicable. If something is contemptible, it is deserving of contempt. 

• Spreading gossip is contemptible. 
• All terrorists are contemptible. 

Contemptuous means feeling contempt for someone or something.

• I am contemptuous of all terrorists. (= I feel contempt for all terrorists.)
• Snobs are usually contemptuous of people they feel to be inferior to them.