/ Dictionary / Index J Jerusalem thorn: Meaning and Definition of Find definitions for: Jeru'salem thorn' Pronunciation: [key] See under a spiny tropical American tree, Parkinsonia aculeata, of the legume family, having long clusters of large yellow flowers. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. Jerusalem oak Jespersen Related Content Daily Word Quiz: rustic Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language