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 of maniacal

• psychotic
• insane
• mad
• crazy
• mental
• crazed

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

An encounter with Ivy leads to Ollie touching a glowing pod — a remnant of majestic creatures that look like a cross between a tree and an elephant who are said to have been banished from The Valley by a maniacal Fire Wolf. —Tribune News Service, Baltimore Sun, 4 May 2026

There’s one sound on earth that will never get old, and that’s Johnny Knoxville’s maniacal cackle when someone has been injured. —Fran Hoepfner, Vulture, 27 Apr. 2026

Bones is a pretty stellar action heroine, if only for her rah-rah speeches and her maniacal laughter in the face of men who seek to control her. —Siddhant Adlakha, Variety, 14 Mar. 2026

Even when discussing this premise, his maniacal desire to win seeps through. —Zach Berman, New York Times, 13 Mar. 2026

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