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K–T boundary

noun

Definition of K–T boundary

  1. :  the transition between the Cretaceous and Tertiary periods of geologic time characterized by a mass extinction of many forms of life including the dinosaurs; also :  a geologic stratum marking this boundary



Origin and Etymology of k–t boundary

K (alternative for C as abbreviation for Cretaceous) + Tertiary


First Known Use: 1983


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