A liquid added to water in car radiators to prevent it from freezing in cold weather and from boiling in hot weather.
From 'anti-' (against) plus 'freeze'. Created as a word in the early 1900s when automobiles became common. The chemical compounds themselves were developed around the same time.
Before antifreeze was invented, people in cold climates had to drain their entire car radiator every winter or the water would freeze and crack the engine—it's a perfect example of chemistry solving real problems.
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