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1. Botany
a. A modified branch in the form of a sharp woody structure.
b. Any of various other sharp protuberances, such as a spine.
c. Any of various shrubs, trees, or woody plants bearing such sharp structures.
2. Any of various sharp protuberances on an animal.
3. One that causes sharp pain, irritation, or discomfort: He is a thorn in my side.
4. The runic letter þ, used in Old English, Middle English, and Old Norse manuscripts to represent both the voiceless sound (th) of Modern English thin and the voiced sound (th) of Modern English this, and in modern Icelandic orthography to represent the voiceless sound (th).

[Middle English, from Old English.]

thorn′less adj.
American Heritage® Dictionary of the English Language, Fifth Edition. Copyright © 2016 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.
ThesaurusAntonymsRelated WordsSynonymsLegend:
Adj.1.thornless - lacking thorns
unarmed - (used of plants or animals) lacking barbs or stings or thorns
Based on WordNet 3.0, Farlex clipart collection. © 2003-2012 Princeton University, Farlex Inc.


[ˈθɔːnlɪs] ADJsin espinas
Collins Spanish Dictionary - Complete and Unabridged 8th Edition 2005 © William Collins Sons & Co. Ltd. 1971, 1988 © HarperCollins Publishers 1992, 1993, 1996, 1997, 2000, 2003, 2005


adjohne Dornen
Collins German Dictionary – Complete and Unabridged 7th Edition 2005. © William Collins Sons & Co. Ltd. 1980 © HarperCollins Publishers 1991, 1997, 1999, 2004, 2005, 2007
References in classic literature ?
A few aloe plants and some chance-sown pellitory grew on the tops of the square pillars of the gates, which all but concealed the stems of a couple of thornless acacias that raised their tufted spikes, like a pair of green powder-puffs, in the yard.
You can buy thornless varieties of blackberry bushes, with a good yield, for your garden.
Sunshine is at a minimum in a yard with a large crabapple and thornless honeylocust trees.
Thornless cultivars 'Inermis' and 'Serena' are ideal for high-traffic areas, while spinier forms would serve well as intruder deterrent.
There is a yellow form and a white form, and this rose is thornless.
Picking a gallon of black raspberries takes hours of finessing oneself through razor-sharp brambles, but you can shake a gallons worth of mulberries out of a couple of pleasantly thornless adult trees in 10 minutes.
'Soft Caress' is a new cultivar, with thornless and slender leaves giving a more oriental and delicate appearance.
Along her path, guests presented her with long-stemmed thornless red roses.
Strik recommends: Trailing blackberries: New thornless Columbia Star and old favorites Marion and Boysen Erect, late-season thornless blackberries: Navaho Semi-erect, last-season blackberries: Triple Crown Summer-bearing red raspberries: new Cascade Delight and Chemainus Yellow raspberries: New Cascade Gold and older favorite Meeker Everbearing (also called primocane-fruiting) raspberries: Vintage is a new red; Anne is the best yellow Black raspberries: Jewel For more information about growing caneberries, check out these OSU Extension publications: "Growing Blackberries in Your Home Garden" "Growing Raspberries in Your Home Garden" "Blackberry Cultivars for Oregon" "Raspberry Cultivars for the Pacific Northwest" - Oregon State University Extension Service