What is the meaning of Borax?

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.

The sodium salt of boric acid, Na2B4O7, either anhydrous or with 5 or 10 molecules of water of crystallization; sodium tetraborate.

Cheap or tawdry furniture or other works of industrial design.

To treat with borax.

borax

Source: wiktionary.org