The act or process of making something sour (acidifying), or changing into an acid.(noun)
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Use "acidification" in a sentence
"Predicting the long-term acidification trends in small subarctic lakes using diatoms."
"Over-fishing, now, and the long-term acidification of the oceans due to carbon dioxide, are far more serious problems ... or I should say, are serious problems, because whaling isn't one."
"Ocean acidification is happening about ten times faster today than it did 55 million years ago, when it preceded the mass extinction of much of the planet’s marine life."