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K-T boundary

noun

Definition of K-T boundary

: 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

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Origin and Etymology of k-t boundary

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

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kt
KT
K-T boundary
KTL

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