noun (1)
\ ˈlün How to pronounce loon (audio) \

Definition of loon

 (Entry 1 of 2)

1 : lout, idler
2 chiefly Scotland : boy
3a : a crazy person
b : simpleton


noun (2)

Definition of loon (Entry 2 of 2)

: any of several large birds (genus Gavia of the family Gaviidae) of Holarctic regions that feed on fish by diving and have their legs placed far back under the body for optimal locomotion underwater

Illustration of loon

Illustration of loon

Noun (2)

In the meaning defined above

First Known Use of loon

Noun (1)

15th century, in the meaning defined at sense 1

Noun (2)

1634, in the meaning defined above

History and Etymology for loon

Noun (1)

Middle English loun

Noun (2)

of Scandinavian origin; akin to Old Norse lōmr loon

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Time Traveler for loon

Time Traveler

The first known use of loon was in the 15th century

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Cite this Entry

“Loon.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/loon. Accessed 7 Mar. 2021.

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More Definitions for loon


\ ˈlün How to pronounce loon (audio) \

Kids Definition of loon

: a large diving bird that eats fish and has a black head and a black back spotted with white

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More from Merriam-Webster on loon

Thesaurus: All synonyms and antonyms for loon

Nglish: Translation of loon for Spanish Speakers

Britannica.com: Encyclopedia article about loon

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