loon

¹ American  

[loon] / lun /

noun

1. any of several large, short-tailed, web-footed, fish-eating diving birds of the genus Gavia, of the Northern Hemisphere.

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loon ² American  

[loon] / lun /

noun

1. a crazy or simple-minded person.

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loon ¹ British  

/ luːn /

noun

1. informal a simple-minded or stupid person

2. dialect a lad

3. archaic a person of low rank or occupation (esp in the phrase lord and loon )

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loon ² British  

/ luːn /

noun

1. the US and Canadian name for diver

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Etymology

Origin of loon¹

First recorded in 1625–35; perhaps alteration of loom ³

Origin of loon²

1400–50; late Middle English lowen, perhaps < Old Norse lūinn worn, tired; later influenced by loon ¹ and loony ¹

Example Sentences

“Thanks for reading” was the suggested reply to someone who called me a hopeless loon and another guy who wondered why anybody would read my “dumb column.”

From Los Angeles Times • Mar. 14, 2026

In the season finale, Shane and Ilya steal away to Shane’s remote cottage on a lake north of Ottawa, where Ilya freaks out when he first hears the cry of a loon.

From The Wall Street Journal • Jan. 22, 2026

As for Foster, who first snagged my attention as the pathetic loon in “Alpha Dog,” he knows how to play a hiss-worthy heel.

From Los Angeles Times • Sep. 11, 2025

Officials didn’t pick any of the most popular designs submitted online that included options like a loon — the state bird — with lasers for eyes.

From Seattle Times • May 11, 2024

The birds—well, they’re some kind of duck . . . or loon?

From "Legendary Frybread Drive-In" by Cynthia Leitich Smith