ma·​ni·​a·​cal | \mə-ˈnī-ə-kəl \
variants: or less commonly maniac \ˈmā-​nē-​ˌak \

Definition of maniacal 

1 : affected with or suggestive of madness maniacal laughter maniacal energy a maniacal killer

2 : characterized by ungovernable excitement or frenzy : frantic a maniacal mob maniacal fans

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Other Words from maniacal

maniacally \mə-​ˈnī-​ə-​k(ə-​)lē \ adverb

Synonyms & Antonyms for maniacal


balmy, barmy [chiefly British], bats, batty, bedlam, bonkers, brainsick, bughouse [slang], certifiable, crackbrained, cracked, crackers, crackpot, cranky [dialect], crazed, crazy, cuckoo, daffy, daft, demented, deranged, fruity [slang], gaga, haywire, insane, kooky (also kookie), loco [slang], loony (also looney), loony tunes (or looney tunes), lunatic, mad, mental, meshuga (or meshugge), moonstruck, non compos mentis, nuts, nutty, psycho, psychotic, scatty [chiefly British], screwy, unbalanced, unhinged, unsound, wacko (also whacko), wacky (also whacky), wud [chiefly Scottish]


balanced, compos mentis, sane, sound, uncrazy

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Examples of maniacal in a Sentence

the movie's villain was a just a clichéd axe-wielding nutcase with a maniacal laugh

Recent Examples on the Web

In her shtetl, only young boys were indulged in their maniacal pursuit of mastery that led them to spend every waking moment poring over the Talmud. WSJ, "Give No Triple Points for ‘Gender Differences’," 22 Nov. 2018 And when the witches arrive, everyone but Langdon and his maniacal nanny robot (Kathy Bates) are killed off or forgotten. Alex Abad-santos, Vox, "American Horror Story: Apocalypse was somehow both absolutely nuts and largely forgettable," 18 Nov. 2018 Smith, who won a promotion for his loyalty to Heinrich Himmler (played with maniacal glee by Kenneth Tigar), is seen as a threat to American Nazi Party founder George Lincoln Rockwell (David Furr), the highest-ranking Nazi in North America. Samantha Nelson, The Verge, "Season 3 of The Man in the High Castle doubles down on science fiction — and stumbles," 27 Sep. 2018 The discovery of all 12 boys alive brought with it joy and a maniacal focus on rescue. David Grossman, Popular Mechanics, "All 12 Thai Boys Rescued From Cave," 10 July 2018 But when the group is radically misdirected by a seriously Super-Villain and his maniacal plan to take over the Earth, things really go awry. Milwaukee Journal Sentinel, "Advance Movie Screening for the Family," 2 July 2018 Hardy and Wyatt cut an entertaining promo on Raw, and Wyatt connected Hardy’s contagious maniacal laughing to the contagious aspects of fear. Justin Barrasso,, "The Week in Wrestling: Tama Tonga Says Bullet Club Civil War ‘Has Been a Long Time Coming’," 11 July 2018 Como, the once maniacal, me-hating escape artist, settled into a serene and even affectionate middle age, his morning bed visits and metronomic tail wags for food and walks and nightly treats a steady backbeat to our empty-nest life. Steven Winn,, "A loving family remembers the zeitgeist of Como the dog," 2 July 2018 This was most evident in how participants discussed medieval religion with disdain, often envisioning illiterate people universally believing whatever came from a maniacal Catholic Church, even when a film conflicted with this notion. Scott Manning,, "Paul B. Sturtevant's 'Middle Ages': Learning a little history from popular culture," 1 May 2018

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'maniacal.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

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First Known Use of maniacal

1526, in the meaning defined at sense 1

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Statistics for maniacal

Last Updated

5 Dec 2018

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Time Traveler for maniacal

The first known use of maniacal was in 1526

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More Definitions for maniacal


ma·​ni·​a·​cal | \mə-ˈnī-ə-kəl \
variants: also maniac \ˈmā-​nē-​ak \

Medical Definition of maniacal 

: manic

Other Words from maniacal

maniacally \mə-​ˈnī-​ə-​k(ə-​)lē \ adverb

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More from Merriam-Webster on maniacal

Rhyming Dictionary: Words that rhyme with maniacal

Thesaurus: All synonyms and antonyms for maniacal

Spanish Central: Translation of maniacal

Nglish: Translation of maniacal for Spanish Speakers

Britannica English: Translation of maniacal for Arabic Speakers

Comments on maniacal

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to make faulty or ineffective

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