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K–T boundary


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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