borax

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

• noun A hydrated sodium borate, Na₂B₄O₇·10H₂O, an ore of boron, that is used as a cleaning compound.
• noun Cheap merchandise, especially tasteless furnishings.

from The Century Dictionary.

• noun Sodium tetraborate or pyroborate, Na₂B₄O₇ + 10H₂O, a salt formed by the union of boracic acid and soda.

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

• noun A white or gray crystalline salt, with a slight alkaline taste, used as a flux, in soldering metals, making enamels, fixing colors on porcelain, and as a soap. It occurs native in certain mineral springs, and is made from the boric acid of hot springs in Tuscany. It was originally obtained from a lake in Thibet, and was sent to Europe under the name of tincal. Borax is a pyroborate or tetraborate of sodium, Na2B4O7.10H2O.
• noun (Chem.) See Bead, n., 3.

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

• noun A white or gray/grey crystalline salt, with a slight alkaline taste, used as a flux, in soldering metals, making enamels, fixing colors/colours on porcelain, and as a soap, etc.
• noun chemistry The sodium salt of boric acid, Na2B4O7, either anhydrous or with 5 or 10 molecules of water of crystallisation; sodium tetraborate.
• adjective Cheap or tawdry, referring to furniture or other works of industrial design.

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

• noun an ore of boron consisting of hydrated sodium borate; used as a flux or cleansing agent