A derogatory term for someone who has said or done something stupid or highly impractical, suggesting a lack of touch with reality or debilitated mental faculties. The term originates with mentally disabled or retarded children involved in a "special education" program at an American public school (similar programs no doubt exist elsewhere in the world). Typically, these children are brought to school in a separate bus that can carry wheelchairs. This bus is usually not nearly as long as the standard schoolbus, and thus is referred to as the "short bus." So if John tried to PUSH on the door marked PULL, he would be called "special... you know, short-bus special."