borax

¹ American  

[bawr-aks, -uhks, bohr-] / ˈbɔr æks, -əks, ˈboʊr- /

noun

plural

boraxes, boraces

1. a white, water-soluble powder or crystals, hydrated sodium borate, Na 2 B 4 O 7 ⋅10H 2 O, occurring naturally or obtained from naturally occurring borates; tincal: used as a flux, cleansing agent, in the manufacture of glass, porcelain, and enamel, and in tanning.

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borax ² American  

[bawr-aks, -uhks, bohr-] / ˈbɔr æks, -əks, ˈboʊr- /

noun

1. cheap, showy, poorly made merchandise, especially cheaply built furniture of an undistinguished or heterogeneous style.

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borax British  

/ ˈbɔːræks /

noun

1. Also called: tincal.  a soluble readily fusible white mineral consisting of impure hydrated disodium tetraborate in monoclinic crystalline form, occurring in alkaline soils and salt deposits. Formula: Na 2 B 4 O 7 .10H 2 O

2. pure disodium tetraborate

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borax Scientific  

/ bôr′ăks′ /

1. A white, crystalline powder and mineral used as an antiseptic, as a cleansing agent, and in fusing metals and making heat-resistant glass. The mineral is an ore of boron and also occurs in yellowish, blue, or green varieties. Chemical formula: Na ₂ B ₄ O ₇ ·10H ₂ O.

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Etymology

Origin of borax¹

1350–1400; < Medieval Latin ≪ dialectal Arabic būraq < Middle Persian būrag; replacing Middle English boras < Middle French < Medieval Latin borax

Origin of borax²

An Americanism dating back to 1940–45; of uncertain origin

Example Sentences

I intend to view him as the ultimate borax man for the remainder of his time in office, and I invite you to do likewise.

From The Wall Street Journal • Dec. 18, 2025

The fire, one of two that day, occurred just after midnight April 4 behind the Borax Museum and destroyed a wooden wagon used to transport borax out of Death Valley in the late 1800s.

From Los Angeles Times • May 15, 2024

Experts say social media users appear to be conflating boron, a naturally occurring mineral, with borax, which is also naturally occurring and is produced when boron is combined with sodium, hydrogen and oxygen.

From Seattle Times • Jul. 28, 2023

The LD50 for borax in rats is about 5g per kilogram of body weight.

From Salon • Jul. 26, 2023

Fat, kindly Dr. Cuevas attempted to treat her with pills of his own devising, with vitamins in syrup and throat swabbings with borax honey, but all to no apparent effect.

From "The House of the Spirits: A Novel" by Isabel Allende