bo·ron /ˈborˌɑn, ˈbɔr-/
 硼


 bo·ron /ˈbo(ə)rˌɑn, ˈbɔ(ə)r-/ 名詞
 硼


 Bo·ron n.  Chem. A nonmetallic element occurring abundantly in borax. It is reduced with difficulty to the free state, when it can be obtained in several different forms; viz., as a substance of a deep olive color, in a semimetallic form, and in colorless quadratic crystals similar to the diamond in hardness and other properties. It occurs in nature also in boracite, datolite, tourmaline, and some other minerals. Atomic number 5. Atomic weight 10.81. Symbol B.

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 boron
      n : a trivalent metalloid element; occurs both in a hard black
          crystal and in the form of a yellow or brown powder [syn:
           B, atomic number 5]


 boron
 Symbol: B
 Atomic number: 5
 Atomic weight: 10.811
 An element of group 13 of the periodic table. There are two allotropes,
 amorphous boron is a brown power, but metallic boron is black. The
 metallic form is hard (9.3 on Mohs' scale) and a bad conductor in room
 temperatures. It is never found free in nature. Boron-10 is used in
 nuclear reactor control rods and shields. It was discovered in 1808 by Sir
 Humphry Davy and by J.L. Gay-Lussac and L.J. Thenard.