Dis-  prefix forming nouns, adjectives, and verbs implying: 1 negation or direct opposite (dishonest; discourteous). 2 reversal (disengage; disorientate). 3 removal of a thing or quality (dismember; disable). 4 separation (distinguish). 5 completeness or intensification (disgruntled). 6 expulsion from (disbar). [french des- or latin dis-]