borax

From Middle English boras, from Anglo-Norman boreis, from Medieval Latin borax, baurach (“borax”), from Arabic بَوْرَق (bawraq), from Middle Persian bwlk' (bōrag), which yielded Persian بوره (bure).

• IPA^(key): /ˈbɔː.ɹæks/

• Audio (Southern England):

  (file)

  • (US) IPA^(key): /ˈbɔɹ.æks/
• Rhymes: -ɔːɹæks

borax (usually uncountable, plural boraxes or boraces)

1. 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.
   • 2025 March 13, Jillian Tracy, “Wash your laundry problems down the drain with these 18 expert-approved products”, in CNN‎^[1]:

     “The best way to clean the machine is to put a pound of borax and a gallon of vinegar in the machine and run the longest, hottest cycle you have,” he says.

2. (inorganic chemistry) The sodium salt of boric acid, Na₂B₄O₇, either anhydrous or with 5 or 10 molecules of water of crystallization; sodium tetraborate.
3. (sometimes attributive) Cheap or tawdry furniture or other works of industrial design.
   • 1977, Harlan Ellison, Jeffty is Five:

     Furniture isn't made to last thirty years or longer because they took a survey and found that young homemakers like to throw their furniture out and bring in all new, color-coded borax every seven years.

• E285 when used as a preservative

borax (third-person singular simple present boraxes, present participle boraxing, simple past and past participle boraxed)

1. (transitive) To treat with borax.

• David Barthelmy (1997–2025) “Borax”, in Webmineral Mineralogy Database.
• “borax”, in Mindat.org‎^[2], Hudson Institute of Mineralogy, 2000–2025.
• “borax n.¹”, in Green’s Dictionary of Slang, Jonathon Green, 2016–present
• borax at the Free Dictionary

Borrowed from French borax.

borax n (uncountable)

1. borax