What does glycol mean?
Glycol is a chemical term with two related uses. In general conversation, it usually means ethylene glycol, a colorless and viscous liquid used in automotive antifreeze, refrigeration systems, and numerous industrial processes. Ethylene glycol is also an important chemical feedstock, but it is acutely toxic if swallowed, making accidental poisoning a serious medical concern. In more formal scientific writing, “glycol” can refer to a whole class of organic compounds called diols, each containing two hydroxyl groups. Propylene glycol is another familiar member of this class and is widely used in food, pharmaceutical, and cosmetic products. The word is therefore common in discussions of automotive maintenance, laboratory chemistry, manufacturing, and public health. Its generic technical meaning is broader than its everyday use, which almost always points to ethylene glycol. Although glycols are chemically diverse, the familiar term has become strongly associated with the risks and practical uses of ethylene glycol in particular.
nounA generic name for an organic alcohol with two hydroxyl groups, usually attached to different carbon atoms. The unqualified term is most often used for ethylene glycol, a colorless liquid used in antifreeze, coolant, and chemical manufacturing.
- The substance ethylene glycol, a colorless, viscous, sweet-tasting liquid used chiefly in antifreeze and as an industrial chemical feedstock.
- More generally, any organic alcohol containing two hydroxyl groups, such as propylene glycol.
"The mechanic found a leak in the radiator's ethylene glycol."
"Ethylene glycol is widely used to prevent engine coolant from freezing in cold weather."
"The chemist compared the properties of several glycols before selecting one for the formulation."
The plural is used when referring to several members of the chemical class or to different glycol compounds.
"The researcher compared the environmental persistence of several glycols."
Ethylene glycol sounds unthreatening, but this sweet-tasting antifreeze ingredient can cause severe poisoning in both people and pets.
Reviewed by Deb Chak, Editor. AI-assisted content curated by RJS Tech Solutions LLP.
Where does glycol come from?
The name belongs to the nineteenth-century development of systematic chemical terminology. Its glyc- element reflects the Greek glykys, meaning “sweet,” while the suffix -ol is used in organic chemistry to denote an alcohol. The same Greek root appears in related chemical names such as glucose, glycerol, glycine, and glycogen.
Related word forms
How glycol is actually used
In technical chemistry, a glycol is any dihydric alcohol. In general usage, however, the word usually refers specifically to ethylene glycol, so the broader sense is most likely in scientific or industrial contexts.
Easily confused with glycol
Glycol generally denotes a diol with two hydroxyl groups, whereas glycerol, also called glycerin, is a triol with three hydroxyl groups.