The Collaborative International Dictionary of English v.0.48:

Jewel \Jew"el\ (j[=u]"[e^]l or j[udd]"[e^]l), n. [OE. juel,
   jowel, OF. jouel, juel, joiel, F. joyau, dim. of OF. joie
   joy, jewel, F. joie joy. See Joy.]
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   1. An ornament of dress usually made of a precious metal, and
      having enamel or precious stones as a part of its design.
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            Plate of rare device, and jewels
            Of rich and exquisite form.           --Shak.
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   2. A precious stone; a gem. --Shak.
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   3. An object regarded with special affection; a precious
      thing. "Our prince (jewel of children)." --Shak.
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   4. A bearing for a pivot a pivot in a watch, formed of a
      crystal or precious stone, as a ruby.
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   Jewel block (Naut.), block at the extremity of a yard,
      through which the halyard of a studding sail is rove.
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