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English definition of “keystone”


noun [C] (IMPORTANT PART)    /ˈkiː.stəʊn/ US  /-stoʊn/
the most important part of a plan , idea , etc. on which everything else depends Important and essential thingsInformation and messages
(Definition of keystone noun (IMPORTANT PART) from the Cambridge Advanced Learner's Dictionary & Thesaurus © Cambridge University Press)
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