Definition of adulterate in US English:



[with object]
  • Render (something) poorer in quality by adding another substance, typically an inferior one.

    ‘the meat was ground fine and adulterated with potato flour’
    • ‘The rice stored in their school for the noon meal scheme was found to be adulterated with fine iron particles, urea, bits of mortar and what not.’
    • ‘His grin widened, but it was adulterated with some apprehension.’
    • ‘A yellow variety which stains water and has a faint odor is adulterated with the horned-poppy (glaucium).’
    • ‘Ground pepper was adulterated with powdered bones.’
    • ‘Legal problems arise when a dishonest producer adulterates the product by substituting synthetic vanillin for natural vanillin without properly identifying the flavoring on the label.’
    • ‘It was illegally added to chilli powder imported in 2001 by a firm in Hull which again did not know the banned substance was present, apparently after producers in India adulterated products with the red dye.’
    • ‘In Europe in the middle ages, even butter and bread were often adulterated, a practice by which inferior or even dangerous materials were added to the ingredient list.’
    • ‘Pot smokers short on time can use a variety of methods to avoid testing positive, such as diluting their urine by drinking a lot of water, substituting someone else's urine, or adulterating their sample with masking agents.’
    • ‘22 karat gold was invariably adulterated and actually only 20 or even 18 karat gold.’
    • ‘In most cases, these substances are adulterated with other chemicals and pose risks of overdose.’
    • ‘The authorities, especially, the health department, should take stringent action against those who are adulterating food.’
    • ‘In retaliation, she poisoned the birthday cake of his nine-year-old daughter by adulterating the batter with juice from oleander leaves.’
    • ‘The significant feature is that it is still the natural derivative of the plant, and, save exceptionally, it is not adulterated by the addition of any further substances.’
    • ‘The Rajasthan Oil Industries Association, for instance, demanded a government inquiry and insisted that punitive action be taken against those found guilty of adulterating the oil supply.’
    • ‘Some preparations are adulterated with phenylbutazone, ephedrine, aminopyrine or mandrake root.’
    • ‘The contaminated chilli powder has been imported from India, where certain producers have been adulterating their product with the red dye.’
    • ‘It is supposed to be extra pure, but some believe that it is often adulterated with much cheaper, commercial, hexane, which is not pure and contains various hazardous substances such as the toxic benzene.’
    • ‘Some wine-makers throughout history sought to enhance either the quality or quantity of their product by adulterating the basic raw material, grapes, with other products.’
    • ‘Ghee is adulterated to the extent of 80 to 85 percent with Vanaspati.’
    • ‘Africa also needs adequate regulatory supervision: formal mechanisms which ensure that drugs are not adulterated by the time they reach patients.’
    make impure, degrade, debase, spoil, taint, defile, contaminate, pollute, foul, sully
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Early 16th century (as an adjective): from Latin adulterat- ‘corrupted’, from the verb adulterare.