The Collaborative International Dictionary of English v.0.48:

Precious \Pre"cious\, a. [OF. precious, precius, precios, F.
   pr['e]cieux, L. pretiosus, fr. pretium price, worth, value.
   See Price.]
   1. Of great price; costly; as, a precious stone. "The
      precious bane." --Milton.
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   2. Of great value or worth; very valuable; highly esteemed;
      dear; beloved; as, precious recollections.
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            She is more precious than rules.      --Prov. iii.
                                                  15.
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            Many things which are most precious are neglected
            only because the value of them lieth hid. --Hooker.
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   Note: Also used ironically; as, a precious rascal.
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   3. Particular; fastidious; overnice; overrefined. Cf.
      Pr['e]cieuse, Preciosity.
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            Lest that precious folk be with me wroth. --Chaucer.
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            Elaborate embroidery of precious language.
                                                  --Saintsbury.
      [Webster 1913 Suppl.]

   Precious metals, the uncommon and highly valuable metals,
      esp. gold and silver.

   Precious stones, gems; jewels.
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