Separation anxiety disorder: Excessive anxiety concerning separation from home or from those to whom a child is attached. The child may develop excessive worrying to the point of being reluctant or refusing to go to school, being alone, or sleeping alone. The child may also experience repeated nightmares and complaints of physical symptoms such as headaches, stomach aches, nausea, or vomiting.
Separation anxiety disorder is persistence of a normal developmental stage that many children experience when separated from their primary care giver (usually the mother) between 8 and 14 months. See also: Separation anxiety.