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Synonyms

overactive

American  
[oh-ver-ak-tiv] / ˌoʊ vərˈæk tɪv /

adjective

  1. exceptionally or excessively active; too active.

overactive British  
/ ˌəʊvərˈæktɪv /

adjective

  1. inordinately active

  2. (of the thyroid or adrenal gland, nervous system, etc) functioning at too high a capacity

"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Other Word Forms

Etymology

Origin of overactive

First recorded in 1640–50; over- + active

Example Sentences

Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.

Koy, the son of a white father and Filipina mother, saw comedy as a way to channel an overactive personality and need to make people laugh into a career.

From Los Angeles Times • Mar. 5, 2026

"I'm a fierce perfectionist and there is an overactive, hugely self-critical voice in my head - my whole life is an exercise in trying to shake that," he says.

From BBC • Dec. 31, 2025

Additional work will also explore how disease-related declines in PIP2 remove this regulatory control, allowing Piezo1 to remain overactive and impair cerebral blood flow.

From Science Daily • Dec. 25, 2025

The company launched a new product for overactive bladder called Altaviva.

From Barron's • Nov. 18, 2025

It might be my overactive imagination, but Ren’s smile seems tighter than everyone else’s, his happiness for me strained.

From "Warcross" by Marie Lu

Definitions and idiom definitions from Dictionary.com Unabridged, based on the Random House Unabridged Dictionary, © Random House, Inc. 2023

Idioms from The American Heritage® Idioms Dictionary copyright © 2002, 2001, 1995 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company.