eustress
n. the positive stress response, involving optimal levels of stimulation: a type of stress that results from challenging but attainable and enjoyable or worthwhile tasks (e.g., participating in an athletic event, giving a speech). It has a beneficial effect by generating a sense of fulfillment or achievement and facilitating growth, development, mastery, and high levels of performance. Compare distress. [first described by Hungarian-born Canadian endocrinologist Hans Selye (1907–1982)]