Hyperactivity refers to a term that describes a higher than normal level of activity. This may apply to behavior, and an organ can also be described as hyperactive if it is more active than usual.

Hyperactivity refers to a behavior, mostly seen in children, that is marked by high levels of activity and restlessness. Hyperactivity is characterized as excessive restlessness and overactivity one of the primary characteristics of Attention -deficit/hyperactivity disorder (ADHD). Hyperactivity should nNot to be confused with misbehavior or with normal high-activity levels that occur during childhood.

Other /More definition:
Hyperactivity refers to a motor pattern involving abnormally energized physical activity that is usually characterized by quick movements and fast talking.