thorn

n. sharp nub, prickle, spine

Thorn has several meanings:Thorn, a sharp structure or growth on plants, see spine (botany)Thorn treeCommon hawthorn, Crataegus monogynaThorn (letter) (Þ, þ), a letter in the Anglo-Saxon and Icelandic alphabets
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Noun
1. something that causes irritation and annoyance; "he's a thorn in my flesh"
(synonym) irritant
(hypernym) annoyance, bother, botheration, pain, infliction, pain in the neck, pain in the ass
2. a sharp-pointed tip on a stem or leaf
(synonym) spine, prickle, pricker, sticker
(hypernym) aculeus
(hyponym) glochidium, glochid
3. a Germanic character of runic origin
(hypernym) rune, runic letter

(v. t.)
To prick, as with a thorn.
  

(n.)
The name of the Anglo-Saxon letter /, capital form /. It was used to represent both of the sounds of English th, as in thin, then. So called because it was the initial letter of thorn, a spine.
  

(n.)
Fig.: That which pricks or annoys as a thorn; anything troublesome; trouble; care.
  

(n.)
Any shrub or small tree which bears thorns; especially, any species of the genus Crataegus, as the hawthorn, whitethorn, cockspur thorn.
  

(n.)
A hard and sharp-pointed projection from a woody stem; usually, a branch so transformed; a spine.
  

a thorn
  

a thorn
  

a thorn; summer; an end
  

keeper; thorn; dregs
  

guardian; thorn
  

thorn; dregs