(idiomatic) A persistent difficulty or something very annoying that will not go away.

Datura spp., especially / Crataegus spp. / Solanum incanum, native to Africa and Asia

plural of Christ's thorn

Paliurus spina-christi, a deciduous shrub or small tree of the Mediterranean and parts of Asia, with spiny shoots.

The shrub Paliurus spina-christi, native to the Eastern Hemisphere. / The shrub Parkinsonia aculeata, native to the Western Hemisphere.

(Christianity) The crown made of a thorny plant that Christ was forced to wear before his Crucifixion, in mocking reference to his alleged status as ‘king of the Jews’, or a representation of this.

plural of Jerusalem thorn

plural of thorn apple

plural of crown of thorns

The plant Christ's thorn, Paliurus spina-christi.