thorn

noun

ˈthȯrn 

often attributive

1

a

: 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\

thorned

ˈthȯrnd 

adjective

thornless

ˈthȯrn-ləs 

adjective

thornlike

ˈthȯrn-ˌlīk 

adjective

Synonyms

• headache
• nuisance
• irritant
• frustration
• rub

Examples of thorn in a Sentence

your constant questions are a thorn in my side

Recent Examples on the Web

And with a team that has not been the biggest thorn in their side over the last 15 seasons. —Jon MacHota, New York Times, 24 Sep. 2025

Though often a thorn in conservatives’ side, Kennedy nevertheless regularly voted with the court’s right-leaning bloc. —Maureen Groppe, USA Today, 23 Sep. 2025

For almost 30 years, the Golden Watchdog and Fleece Awards have been a key fundraiser for the nonprofit — and a thorn in the side of public agencies on the receiving end of unwelcome attention for wasting government resources. —Jeff McDonald, San Diego Union-Tribune, 22 Sep. 2025

Despite not scoring, Dembélé was a constant thorn in the side of Inter Milan and set up two goals while also helping to create another during his side’s 5-0 win. —David Close, CNN Money, 22 Sep. 2025

Word History

Etymology

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

First Known Use

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

Phrases Containing thorn

• a thorn in the/someone's flesh/side
• Christ's-thorn
• Christ-thorn
• Jerusalem thorn
• thorn apple

Rhymes for thorn

• borne
• bourn
• bourne
• corn
• morn
• mourn
• porn
• scorn
• shorn
• sworn
• torn
• warn

Kids Definition

thorn

noun

ˈthȯ(ə)rn 

1

: a woody plant bearing sharp processes (as prickles or spines)

especially : hawthorn

2

: a sharp stiff process on a plant

especially : a stem modified into a short, stiff, and leafless sharp point

3

: something or someone that causes distress or irritation

—often used in the phrase thorn in one's side

thorned

ˈthȯ(ə)rnd 

adjective

thornless

ˈthȯ(ə)rn-ləs 

adjective