from The American Heritage® Dictionary of the English Language, 5th Edition.

  • noun A nonmetallic element that is amorphous and brown or crystalline and black, and is extracted chiefly from kernite and borax and used in flares, propellant mixtures, nuclear reactor control elements, abrasives, and hard metallic alloys. Atomic number 5; atomic weight 10.811; melting point 2,075°C; boiling point 4000°C; specific gravity (crystal) 2.34, (amorphous) 2.37; valence 3. cross-reference: Periodic Table.

from The Century Dictionary.

  • noun Chemical symbol, B; atomic weight, 11. A chemical element belonging to the group of non-metals.

from the GNU version of the Collaborative International Dictionary of English.

  • noun (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.

from Wiktionary, Creative Commons Attribution/Share-Alike License.

  • noun The chemical element (symbol B) with an atomic number of 5; a metalloid

from WordNet 3.0 Copyright 2006 by Princeton University. All rights reserved.

  • noun a trivalent metalloid element; occurs both in a hard black crystal and in the form of a yellow or brown powder


from The American Heritage® Dictionary of the English Language, 4th Edition

[bor(ax) + (carb)on.]

from Wiktionary, Creative Commons Attribution/Share-Alike License

From stem of borax + -on ("ending used to form names of substances")


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  • B.

    December 16, 2007