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Browse the Dictionary:: A; B; C; D; E; F; G; H; I; J; K; L; M; N; O; P; Q; R; S; T; U; V; W; X; Y; Z; #

keystone

Entry Word:: keystone
Function:: noun

Text: an immaterial thing upon which something else rests<complete honesty is the keystone of our friendship>— see base 1

Learn more about "keystone" and related topics at Britannica.com

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