Learner's definition of JEWEL
a valuable stone (such as a ruby or diamond) that has been cut and polished
a piece of jewelry (such as a necklace or a bracelet) that is made of valuable metal and precious stones
— usually plural
someone or something that is highly valued or admired
see also crown jewel
This painting is the jewel in our gallery.
She's a jewel.
The building is regarded as one of the jewels of modern architecture.
He owns several successful businesses but this company is the jewel in the crown. [=this company is the most valuable/important/admired]
the part of a watch that is made of a crystal or a precious stone
the family jewels
jewelry that has been passed from one generation to another
informal + humorous
a man's sexual organs