a sharp excrescence on a plant, esp. a sharp-pointed aborted branch; spine; prickle.

any of various thorny shrubs or trees, esp. the hawthorns belonging to the genus Crataegus, of the rose family.

the wood of any of these trees.

a runic character (þ), borrowed into the Latin alphabet and representing the initial th sounds in thin and they in Old English, or thin in modern Icelandic.

something that wounds, annoys, or causes discomfort.

to prick with a thorn; vex. ?

thorn in one's side or flesh

a source of continual irritation or suffering

That child is a thorn in the teacher's side.

noun

needle , prickle , spine , trial , annoyance , brier , discomfort , infliction , irritation , pain , plague , spike , splint , spur , torment , trouble , vexation