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 spiny 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 of thorn

• 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

More recently, Hannah Hidalgo has been a thorn in the Huskies’ sides, though UConn got past ND in the Elite Eight last March. — Dom Amore, Hartford Courant, 19 Sep. 2026

Oil, which in recent weeks has been a thorn in the stock market's side, provided the first source of relief Monday. — Alexa Lomonaco, CNBC, 14 Sep. 2026

Miami dominated the series against Nashville since Messi’s arrival in 2023, but Nashville has been a thorn in Miami’s side this season. — Michelle Kaufman, Miami Herald, 11 Sep. 2026

Besides a necklace of thorns, which draws small drops of blood, Kahlo appears to be more focused on the relief of healing. — Amy Nicholson, Los Angeles Times, 8 Sep. 2026

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
• morne
• mourn
• porn
• scorn
• shorn
• sworn
• torn

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