propylene glycol

American  

noun

Chemistry.

1. a colorless, viscous, hygroscopic liquid, C 3 H 8 O, used chiefly as a lubricant, as an antifreeze, as a heat transfer fluid, and as a solvent for fats, oils, waxes, and resins.

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propylene glycol British  

noun

1. Systematic name: 1,2-dihydroxypropane.  a colourless viscous hydroscopic sweet-tasting compound used as an antifreeze and brake fluid. Formula: CH 3 CH(OH)CH 2 OH

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propylene glycol Scientific  

1. A colorless, viscous liquid used in antifreeze solutions, in hydraulic fluids, and as a solvent. Unlike ethylene glycol, it is not toxic and is also used in foods, cosmetics, and oral hygiene products. Chemical formula: C ₃ H ₈ O ₂ .

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Etymology

Origin of propylene glycol

First recorded in 1880–85

Example Sentences

Bangor University researcher Dr Ben Exton investigated the impact of de-icing chemicals such as propylene glycol for his PhD.

From BBC • May 10, 2025

The Public Prosecutor said that between October 2021 and February 2022 the company received two batches of propylene glycol, which is used for making cough syrup.

From BBC • Nov. 1, 2023

While, propylene glycol is non-toxic and widely used in medicines, cosmetics and food, ethylene glycol is toxic and used in paint, pens and brake fluid.

From BBC • Nov. 1, 2023

DEG and EG have been used by unscrupulous actors as a substitute for propylene glycol because they are cheaper, according to pharmaceutical manufacturing experts.

From Reuters • Jun. 28, 2023

They include ethylene glycol, propylene glycol, trimethylene glycol, mannitol, sorbitol, dextrans, and seminal-plasma proteins.

From Preservation of Bull Semen at Sub-Zero Temperatures by Friedman, M. E.