Synonyms for Adulterate (same or very similar meaning)
WordNet sense 1 (mixed with impurities):
adulterated, debased
WordNet sense 2 (combined with extraneous elements):
impure
WordNet sense 3 (corrupt, debase, or make impure by adding a foreign or inferior substance; often by replacing valuable ingredients with inferior ones):
debase, dilute, stretch
From the ODE community, based on WordNet
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