a sharp excrescence on a plant, especially a sharp-pointed aborted branch; spine; prickle.
any of various thorny shrubs or trees, especially the hawthorns belonging to the genus Crataegus, of the rose family.
the wood of any of these trees.
a runic character (þ), borrowed into the Latin alphabet and representing the initial th sounds in thin and they in Old English, or thin in modern Icelandic.
something that wounds, annoys, or causes discomfort.
a sharp pointed woody extension of a stem or leaf Compare prickle
any of various trees or shrubs having thorns, esp the hawthorn
the wood of any of these plants
short for thorn moth
a Germanic character of runic origin Þ used in Old and Modern Icelandic to represent the voiceless dental fricative sound of th, as in thin, bath. Its use in phonetics for the same purpose is now obsolete See theta
this same character as used in Old and Middle English as an alternative to edh, but indistinguishable from it in function or sound Compare edh
zoology any of various sharp spiny parts
a source of irritation (esp in the phrases a thorn in one's side or flesh )
before 900; Middle English (noun), Old English; cognate with Dutch doorn, German Dorn, Old Norse thorn, Gothic thaurnus
A thorn is a sharp spike that protrudes from the stem of a plant. Roses are famous for having the sweetest fragrance and the sharpest thorns. Literal thorns, found on bushes and other plants, serve to protect plants from animals that might like to eat them. A "thorn in one's side" is an annoyance or problem: "My neighbors are a thorn in my side, with their constant loud music and crazy parties!" The source of this figurative definition is the Bible's "thorn in the flesh."
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Will it be a case of rose meet thorn?
From Barron's • Apr. 28, 2026
Anthropic’s new model, Claude Mythos, has been the latest thorn in the side of the software sector.
From MarketWatch • Apr. 16, 2026
A thorn in Liverpool's defence, Haaland became just the third Premier League player to score in four or more consecutive home games against the Reds after Chris Sutton and former City forward Sergio Aguero.
From BBC • Apr. 4, 2026
“And that we have somebody that was a former All-Star pitcher, someone that was a thorn in our side as the Padres, and becomes a thorn in the side for other people.”
From Los Angeles Times • Mar. 30, 2026
Alan dives and tags Gloria on the foot, and she howls as she grabs a bush and touches a thorn.
From "Zara’s Rules for Record-Breaking Fun" by Hena Khan
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.
