Specific developmental disorder: A disorder that selectively affects one area of development, sparing essentially all other areas of development.
For example, dysgraphia is one type of specific developmental disorder. In dysgraphia there is inability to write legibly. Problems in dysgraphia may include fine-motor muscle control of the hands and/or processing difficulties. Sometimes occupational therapy is helpful. Most successful students with dysgraphia that does not respond to occupational therapy or extra writing help choose to use a typewriter, computer, or verbal communication.
Specific developmental disorders are as opposed to pervasive developmental disorders (which affect development across the board), dyspraxias that affect multiple systems, cerebral palsy, and metabolic disorders.