Merriam-Webster Collegiate Dictionary - dis-

 prefix  Etymology: Middle English ~, des-, from Anglo-French & Latin; Anglo-French des-, ~, from Latin ~, literally, apart; akin to Old English te- apart, Latin duo two — more at two  1.  a. do the opposite of disestablish  b. deprive of (a specified quality, rank, or object) disfranchise  c. exclude or expel from disbar  2. opposite or absence of disunion disaffection  3. not disagreeable  4. completely disannul  5. by folk etymology dys- disfunction