এখানে শুদ্ধ বানানটি হলো Adulteration. Adulteration (Noun) English Meaning: the action of making something poorer in quality by the addition of another substance. Bangla Meaning: ভেজাল; অপমিশ্রণ; মিশাল।
Source: Oxford Dictionary, Merriam-Webster Dictionary, Bangla Academy Dictionary