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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

  • overactiveness noun
  • overactivity noun

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.

Axonics makes an implantable device that treats bowel and bladder conditions, such as overactive bladder.

From Barron's • Oct. 30, 2025

The scientists also tested the compound in mice with tumors carrying mutations in another cancer-linked gene, HER2, which is often overactive in breast cancer and also connects with PI3K.

From Science Daily • Oct. 19, 2025

“I have a prescription for an overactive bladder.”

From The Wall Street Journal • Oct. 17, 2025

Moriarty, 30, revealed to her Instagram followers on Friday that she was diagnosed last month with Graves’ disease, an autoimmune disorder in which the thyroid becomes overactive.

From Los Angeles Times • Jun. 16, 2025

Noah has an overactive imagination, written on every school report I’ve ever gotten.

From "I'll Give You the Sun" by Jandy Nelson

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.