overactive

adjective

ˌō-vər-ˈak-tiv How to pronounce overactive (audio)
Definition of overactivenext
as in heated
being in a state of increased activity or agitation the boy manages to panic himself by his own overactive imagination

Synonyms & Similar Words

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Antonyms & Near Antonyms

Example Sentences

Examples are automatically compiled from online sources to show current usage. Read More Opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback.
Recent Examples of overactive Thus, people who have overactive versions of PCSK9 have fewer LDL receptors and higher LDL levels in their blood. — Beth Mole, ArsTechnica, 28 May 2026 Sepsis is considered a life-threatening medical emergency that occurs when the body has an extreme, overactive response to an infection, causing the immune system to damage its own tissues and organs, according to the Centers for Disease Control and Prevention. — Steve Reed, Los Angeles Times, 23 May 2026 Studies show the drug works by affecting brain chemicals such as glutamate and dopamine to help calm the overactive signals in the brain linked to agitation. — Dr. Jennifer Miao, ABC News, 1 May 2026 Red or Dark Skin With an overactive thyroid, your circulation increases. — Brandi Jones, Health, 28 Apr. 2026 See All Example Sentences for overactive
Recent Examples of Synonyms for overactive
  1. heated
  2. excited
  3. agitated
  4. hyperactive
Adjective
  • But after choosing to skip the team’s upcoming July 23 White House visit celebrating their 2026 World Series title, the utility veteran found himself at the center of a heated political debate.
    — Alejandro Avila OutKick, FOXNews.com, 21 July 2026
  • The rivalry between New York and Florida — and California and Florida, too — has also become heated as the wealthy have publicly criticized blue states and announced their decisions to relocate.
    — Jacqui Palumbo, CNN Money, 21 July 2026
Definition of heated
Adjective
  • Nguyen was excited to enjoy a warm summer outdoors before the smoke left her hesitant to step outside for her routine runs to the National Mall and daily walks with her dog.
    — Dalia Faheid, CNN Money, 18 July 2026
  • McKeon was excited to explore her chemistry with executive producer Gina Wendkos, who worked on the show alongside Tom Palmer, Jonathan Axelrod, James Widdoes and Amy Sherman-Palladino.
    — Angela Andaloro, PEOPLE, 17 July 2026
Definition of excited
Adjective
  • The bison then appeared to become agitated and began running toward the pair.
    — Sara Smart, CNN Money, 13 July 2026
  • The animal, clearly agitated, appeared to target the man in footage captured Friday at one of the park's campgrounds.
    — Emily Mae Czachor, CBS News, 13 July 2026
Definition of agitated
Adjective
  • Your hyperactive dog catches the scent of a deer and, powered by his hunter's instinct, disappears in the forest.
    — Tereza Pultarova, Space.com, 11 July 2026
  • Of course, Zola was hyperactive in his own way.
    — Lily Meyer, The Atlantic, 18 June 2026
Definition of hyperactive

Browse Nearby Words

overacting
overactive
overacts
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Cite this Entry

“Overactive.” Merriam-Webster.com Thesaurus, Merriam-Webster, https://www.merriam-webster.com/thesaurus/overactive. Accessed 24 Jul. 2026.

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More from Merriam-Webster on overactive

Nglish: Translation of overactive for Spanish Speakers

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