WordReference Random House Unabridged Dictionary of American English © 2026
Hope′ dia′mond,
- Jewelrya sapphire-blue Indian diamond, the largest blue diamond in the world, weighing 44.5 carats and supposedly cut from a bigger diamond that was once part of the French crown jewels: now in the Smithsonian Institution.
- after Henry Philip Hope (died 1839), English gem collector, who once owned it