The word "witch" comes from an old English word "wicce" which means "one who practices magic."  "Wicce" probably comes from a root word meaning "to know" or a similar word meaning "to turn aside."  In Anglo-Saxon times, the word witch could mean a man or a woman. 

     Nowadays, people take it for granted that a witch is a woman, usually old and ugly.  People call a male witch a "wizard."  This word comes from the old word "wise" and "ard."  "Wise" means "to know" and "ard" was an ending people put on word when the word met disapproval, like the word "coward."

     When the word "wizard" just started getting used, it simply meant a man of learning.  Later it came to mean a man with a very special kind of learning, knowledge of the black arts.