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Synonyms

loopy

American  
[loo-pee] / ˈlu pi /

adjective

loopier, loopiest

  1. full of loops.

  2. Slang.

    1. eccentric; crazy; dotty.

    2. befuddled or confused, especially due to intoxication.

  3. Scot. crafty; sly.

loopy British  
/ ˈluːpɪ /

adjective

  1. full of loops; curly or twisted

  2. informal slightly mad, crazy, or stupid

"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

Etymology

Origin of loopy

First recorded in 1815–25; loop 1 + -y 1

Explanation

Someone who's loopy is batty or nutty — in other words, not the picture of mental health. You might get so tired after staying up late to study for a test that you start to act goofy and giggly and a little bit loopy. Even if you are completely sane, you can still act loopy when you're embarrassed or tired or just being silly. You might love the circus because of the loopy music and the painted-on, loopy smiles of the clowns. Or maybe you're a fan of loopy comedies, films that feature characters with harebrained ideas that backfire in ridiculous ways. This informal meaning dates from the early 20th century — earlier, the word meant "deceitful."

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Vocabulary lists containing loopy

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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.

During his intros, Ding offers a loopy little wave to the camera that looks like he’s still getting the hang of it.

From The Wall Street Journal • Apr. 21, 2026

And Enver Chakartash’s costumes are a riot of splashy patterns and extravagant colors, with Damis’s beribonned ensemble and lavender, fur-trimmed boots adding a note of loopy sartorial humor.

From The Wall Street Journal • Dec. 17, 2025

A long, loopy pass from Finn Russell was intercepted in the Argentine 22m and the Pumas raced up the field, only held up by illegal Scotland defence that saw Blair Kinghorn carded.

From BBC • Nov. 16, 2025

Awestruck, Zoë pets the painting and stares at Matt with loopy eyes, thrilled that someone else is experiencing this with her.

From Salon • May 15, 2025

A few had been snatched from envelopes written in the loopy cursive of the coolest granddaughter in world.

From "Look Both Ways" by Jason Reynolds

Definitions and idiom definitions from Dictionary.com Unabridged, based on the Random House Unabridged Dictionary, © Random House, Inc. 2023

Idioms from The American Heritage® Idioms Dictionary copyright © 2002, 2001, 1995 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company.