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Synonyms

maniacal

American  
[muh-nahy-uh-kuhl] / məˈnaɪ ə kəl /

adjective

  1. of or relating to mania or a maniac.


maniacal British  
/ məˈnaɪəkəl /

adjective

  1. affected with or characteristic of mania

  2. characteristic of or befitting a maniac

    maniacal laughter

"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 maniacal

First recorded in 1670–80; maniac + -al 1

Explanation

This one's easy. If someone is maniacal then they're behaving like a maniac. Add an -ly to make it an adverb, and you get maniacally, as in "she's acting maniacally." The noun maniac is almost always used to describe people who do nutty things—serial killers, insane people on the street, crowds at soccer matches. But the adjective maniacal can be more loosely applied to situations, settings, animals, etc. You can use maniacal to describe almost anything that seems wildly crazy or dangerously out of kilter. I don't even remember what the Beatles played that first time on TV. It's the maniacal screaming from the fans that sticks in my head. No movie villain was ever as maniacal as Jason, in Friday the 13th.

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Vocabulary lists containing maniacal

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.

See Examples For:

He also put a maniacal focus on Apple’s supply chain, owing to his prior stint as the company’s chief operating officer.

From MarketWatch ● Apr. 20, 2026

We should only expect more maniacal threats as time goes on.

From Slate ● Apr. 11, 2026

At the Milan Cortina Games, a maniacal Norwegian named Johannes Hoesflot Klaebo has turned the quiet world of Nordic skiing on its head with a frenetic sprinting technique that he concocted with his grandfather.

From The Wall Street Journal ● Feb. 16, 2026

If you’re reading this review of Gore Verbinski’s maniacal farce “Good Luck, Have Fun, Don’t Die” in newsprint, congratulations on being a Luddite.

From Los Angeles Times ● Feb. 12, 2026

Judging from his dilated eyes and his maniacal grin, he didn’t need any more caffeine.

From "The House of Hades" by Rick Riordan

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