NCI Dictionary of Cancer Terms
The NCI Dictionary of Cancer Terms features 7,777 terms related to cancer and medicine.
Browse the dictionary by selecting a letter of the alphabet or by entering a cancer-related word or phrase in the search box.
- listen (HY-per-ak-TIH-vih-tee)
- A higher than normal level of activity. Hyperactivity can be used to describe the increased action of a body function, such as hormone production, or behavior. A person who is hyperactive may seem to be always moving or fidgeting, impulsive, unable to concentrate, and talking too much.