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English definition of “acid”

acid

noun [U] (DRUG)    /ˈæs.ɪd/
slang for LSD (= an illegal drug that makes people see things that do not exist )Specific types of drugDrugs - general wordsSpecific medicines and drugs
(Definition of acid noun (DRUG) from the Cambridge Advanced Learner's Dictionary & Thesaurus © Cambridge University Press)
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