loony

adjective

loo·​ny ˈlü-nē 

variants or less commonly looney

loonier; looniest

: foolish, eccentric

looniness noun

loony noun

plural loonies

Synonyms of loony

• stupid
• silly
• insane
• foolish
• mad
• absurd
• crazy
• lunatic
• idiotic
• irrational

Examples of loony in a Sentence

Every family includes someone who's a little loony.

that's got to be the looniest idea I've ever heard

Recent Examples on the Web

The Loons indeed are loony, but in a calculating way. —Tom Krasovic, San Diego Union-Tribune, 12 Nov. 2025

Dark loony New York comedy, but still. —Bill Goodykoontz, AZCentral.com, 27 Aug. 2025

The Army secretary, acting on the guidance of a loony Trump acolyte, revoked the teaching appointment of — anyone will tell you — one of America’s most skilled nonpartisan cyberwarriors, herself a graduate of West Point. —Thomas L. Friedman, Mercury News, 7 Aug. 2025

None of them care what their grandiose and loony ideas cost ordinary people. —Susan Shelley, Daily News, 16 Apr. 2025

Word History

Etymology

by shortening & alteration from lunatic

First Known Use

1841, in the meaning defined above

Phrases Containing loony

• loony bin
• loony tunes

Rhymes for loony

• looney
• mooney
• muni
• nguni
• puny
• sunni

Kids Definition

loony

adjective

loo·​ny

variants also looney

ˈlü-nē 

loonier; looniest

: very foolish or eccentric

looniness noun

loony noun

Etymology

an altered form of lunatic (adjective)