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English definition of “acid”


noun [C/U]  /ˈæs·ɪd/ us  
chemistry any of various chemical substances that can produce salts, some of which are able to damage whatever they touch


adjective  /ˈæs·ɪd/ us  
sour in taste: The salad dressing has an acid taste. fig. An acid comment/remark is something said or written in strong criticism.
(Definition of acid from the Cambridge Academic Content Dictionary © Cambridge University Press)
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