I.
1.
[so called from the wreath placed on Jesus' head by Roman soldiers who mocked him as “King of the Jews” prior to his crucifixion]
: a severe infliction : unmerited injury
2.
a. : a somewhat climbing bushy spurge ( Euphorbia milii ) of Madagascar that has long thick woody stems covered with stout spines, few leaves mostly restricted to the new growth, and flowers subtended by brilliant scarlet bracts and that is sometimes cultivated in the greenhouse
b. : caraunda
II.
or crown-of-thorns starfish
: a starfish ( Acanthaster planci ) of the Pacific region that is covered with long spines and feeds on coral polyps sometimes causing destruction of coral reefs