noun, often attributive
\ˈthȯrn \

Definition of thorn 

1a : a sharp rigid process on a plant especially : one that is a short, indurated, sharp-pointed, and leafless modified stem — compare prickle, spine

b : any of various sharp spinose structures on an animal

2 : a woody plant bearing sharp impeding processes (such as prickles or spines) especially : hawthorn

3 : something that causes distress or irritation often used in the phrase thorn in one's side

4 : the runic letter þ used in Old English and Middle English to represent either of the fricatives \th\ or \t͟h\ and in Icelandic to represent \th\

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Other Words from thorn

thorned \ˈthȯrnd \ adjective
thornless \ˈthȯrn-ləs \ adjective
thornlike \ˈthȯrn-ˌlīk \ adjective

Examples of thorn in a Sentence

your constant questions are a thorn in my side

Recent Examples on the Web

Waters has positioned herself as a thorn in Trump’s side Waters is 14-term House member who represents California’s 43rd Congressional District, which covers part of Los Angeles. Emily Stewart, Vox, "Maxine Waters could be a serious problem for Trump if Democrats win the House," 5 July 2018 Beautiful foreheads stabbed by real thorns, Anna Wintour has sculpted her hair into a bishop’s hat with mousse, a cape made of Martin Luther’s skin, Benedict is here in a modest swimsuit. Patricia Lockwood, The Cut, "Patricia Lockwood (and Her Mom) Talk Jesus, Fashion, and Who Wore It Best at the Met Gala," 8 May 2018 One character embeds rose thorns in her feet; several have very disordered eating habits; people die too young, go to war and hold in their cells and minds the memories of past trauma. Ramona Ausubel, New York Times, "Flawed, Fragile, Hungry Human Bodies: A.M. Homes’s Stories Get Under the Skin," 4 July 2018 In 2005, the Moorea reefs faced hordes of crown-of-thorn sea stars, which eat coral polyps. National Geographic, "These 38 Coral Reefs Are Thriving, Despite Threats," 18 June 2018 Throughout the past decade Inter have seen Cagliari become quite the thorn in their side, especially at San Siro., "Inter vs Cagliari Preview: Classic Encounter, Key Battle, Team News & More," 16 Apr. 2018 The brainchild of comedian Beppe Grillo, the 5-Star Movement was long considered an itchy thorn in the EU’s side at best, a droll antidote to the sometimes deadening debate at the European Parliament. Washington Post, "Italian election results cast a pall over the European Union," 5 Mar. 2018 How many women have been surprised to receive a green stem bearing a dozen green Brussels sprouts instead of a dozen red roses bearing thorns? Marcy Meffert, San Antonio Express-News, "Elders Express readers’ reactions are sprouting," 16 Feb. 2018 Matt Sanderson, the leader of the political action committee that had been a thorn in the BCS’s side for two years, celebrated the chaos. Ross Dellenger,, "Did the LSU-Alabama Rematch Really Kill the BCS?," 10 July 2018

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'thorn.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

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First Known Use of thorn

before the 12th century, in the meaning defined at sense 2

History and Etymology for thorn

Middle English, from Old English; akin to Old High German dorn thorn, Sanskrit tṛṇa grass, blade of grass

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Phrases Related to thorn

a thorn in the/someone's flesh/side

Statistics for thorn

Last Updated

2 Oct 2018

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Time Traveler for thorn

The first known use of thorn was before the 12th century

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More Definitions for thorn


\ˈthȯrn \

Kids Definition of thorn

1 : a hard sharp leafless point on the stem or branch of a plant (as a rose bush)

2 : a bush or tree that has thorns

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