thorn
//θɔːrn//
Noun
thornSingular
thornsPlural
1
A sharp, pointed projection on a plant stem, typically a modified branch or leaf.
Be careful not to prick your finger on the thorns of the rose bush.
2
A source of continual annoyance or trouble; a persistent problem.
The old computer system has been a thorn in our side for years.
3
A runic letter (þ) used in Old English and Icelandic to represent the sounds /θ/ and /ð/.
The letter thorn (þ) was commonly used in Old English manuscripts.