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English definition of “acid”

acid

noun uk   /ˈæs.ɪd/ us  

acid noun (CHEMICAL)

B2 [C or U] any of various usually liquid substances that can react with and sometimes dissolve other materials: acetic/hydrochloric/lactic acid Vinegar is an acid.

acid noun (DRUG)

[U] slang for LSD (= an illegal drug that makes people see things that do not exist)

acid

adjective uk   /ˈæs.ɪd/ us  

acid adjective (CHEMICAL)

(also acidic) containing acid, or having similar qualities to an acid: an acid taste/smell acid soil

acid adjective (UNKIND)

describes a remark or way of speaking that is cruel or criticizes something in an unkind way: her acid wit When she spoke her tone was acid.
(Definition of acid from the Cambridge Advanced Learners Dictionary & Thesaurus © Cambridge University Press)
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