/ Dictionary / Index H hyperactive: Meaning and Definition of Find definitions for: hy•per•ac•tive Pronunciation: (hī"pur-ak'tiv), [key] — adj. unusually or abnormally active: a company's hyperactive growth; the child's hyperactive imagination. (of children) displaying exaggerated physical activity sometimes associated with neurologic or psychologic causes. hyperkinetic. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. See also: hyperactive (Thesaurus) hyperacidity hyperactivity Related Content Daily Word Quiz: abscond Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language