English version

keystone

From Longman Dictionary of Contemporary English
Related topics: Construction
keystonekey‧stone /ˈkiːstəʊn $ -stoʊn/ noun 🔊 🔊 1 TBC[countable] the large central stone in an arch that keeps the other stones in position2 IMPORTANT[singular] formal the most important part of an idea, belief, or process that influences how it developskeystone of 🔊 The keystone of any personal injury case is medical evidence.
Examples from the Corpus
keystone ofA high level of production has become a keystone of economic security.
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