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English definition of “buffer”


noun (PROTECTION)    /ˈbʌf.ər/ US  //
[C] something or someone that helps protect from harm : I bought a house as a buffer against inflation .Protection and protectorsEnvironmental issues [C] the metal parts at the front and back of a train or at the end of a track , that help protect the train and reduce damage if the train hits somethingTrains and parts of trainsRailways and railway lines [C or U] a chemical that keeps a liquid from becoming more or less acidic Types of chemicalSpecific chemicals, chemical compounds and gasesSubstances and structures in the body
(Definition of buffer noun (PROTECTION) from the Cambridge Advanced Learner's Dictionary & Thesaurus © Cambridge University Press)
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