1. a stiff, sharp-pointed woody projection on the stem or other part of a plant.
▪ a source of discomfort, annoyance, or difficulty; an irritation or obstacle: "the issue has become a thorn in renewing the peace talks"
2. a thorny bush, shrub, or tree, especially a hawthorn.
3. an Old English and Icelandic runic letter, þ or Þ, representing the dental fricatives ð and θ. In English it was eventually superseded by the digraph th.
4. a yellowish-brown woodland moth that rests with the wings raised over the back, with caterpillars that mimic twigs in appearance.
Word OriginOld English, of Germanic origin; related to Dutch doorn and German Dorn.
