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decaffeination

n. The removal of caffeine.

Wikipedia
Decaffeination

Decaffeination is the removal of caffeine from coffee beans, cocoa, tea leaves and other caffeine-containing materials. While soft drinks which do not use caffeine as an ingredient are sometimes described as "decaffeinated", they are better termed "non-caffeinated" because decaffeinated implies that there was caffeine present at one point in time. Decaffeinated drinks contain typically 1–2% of the original caffeine content, and sometimes as much as 20%. Decaffeinated products are commonly termed decaf.