crown of thorns

Short definition from Wiktionary

Noun

1. 1
   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.
2. 2
   A spiny Mediterranean tree, Ziziphus spina-christi.
3. 3
   A spiny spurge, Euphorbia milii, native to Madagascar.
4. 4
   The plant Koeberlinia spinosa.
5. 5
   Ellipsis of crown-of-thorns starfish
6. 6
   A woodworking technique, used in tramp art, in which interlocking pieces are notched to intersect at right angles and form joints and self-supporting objects.