maniacal

adjective

ma·​ni·​a·​cal mə-ˈnī-ə-kəl 

variants or less commonly maniac

ˈmā-nē-ˌak 

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

maniacally

mə-ˈnī-ə-k(ə-)lē 

adverb

Synonyms

• 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
• kookie
• loco [slang]
• loony
• looney
• loony tunes
• looney tunes
• lunatic
• mad
• mental
• meshuga
• meshugge
• meshugah
• meshuggah
• moonstruck
• non compos mentis
• nuts
• nutty
• psycho
• psychotic
• scatty [chiefly British]
• screwy
• unbalanced
• unhinged
• unsound
• wacko
• whacko
• wacky
• whacky
• wud [chiefly Scottish]

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

But there was a hint of the maniacal as that finale began, as if the third movement’s eeriness had lingered. —Zachary Woolfe, New York Times, 24 Nov. 2024

The actor, 28, plays Lucius in director Ridley Scott's sequel to 2000's Gladiator, picking up the story in a tyrannical Rome 16 years after Maximus (Russell Crowe) defeated the maniacal Commodus (Joaquin Phoenix). —Rebecca Aizin, People.com, 20 Nov. 2024

Hechinger and Joseph Quinn play twin maniacal emperors Caracalla and Geta, respectively. —Lauren Huff, EW.com, 20 Nov. 2024

Unbeknownst to Rose, the patient in her death passed on to her a malevolent invisible force that only seems to manifest as visions of people flashing maniacal smiles at her. —Tim Lammers, Forbes, 17 Oct. 2024

Word History

Etymology

Middle French maniaque "mad, frenzied" & its source, Late Latin maniacus + -al entry 1 — more at maniac entry 1

First Known Use

1526, in the meaning defined at sense 1

Kids Definition

maniacal

adjective

ma·​ni·​a·​cal mə-ˈnī-ə-kəl 

variants also maniac

ˈmā-nē-ˌak 

: affected with or suggestive of madness

maniacally

mə-ˈnī-ə-k(ə-)lē 

adverb

Medical Definition

maniacal

adjective

ma·​ni·​a·​cal mə-ˈnī-ə-kəl 

variants also maniac

ˈmā-nē-ak 

: manic

maniacally

mə-ˈnī-ə-k(ə-)lē 

adverb