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English definition of “acid”

acid

noun [C or U] (CHEMICAL)    /ˈæs.ɪd/
B2 any of various usually liquid substances that can react with and sometimes dissolve other materials: acetic/hydrochloric/lactic acid Vinegar is an acid.Types of chemicalSpecific chemicals, chemical compounds and gasesSubstances and structures in the body
(Definition of acid noun (CHEMICAL) from the Cambridge Advanced Learner's Dictionary & Thesaurus © Cambridge University Press)
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