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

First Known Use of K-T boundary

1983, in the meaning defined above

History and Etymology for K-T boundary

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

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Time Traveler for K-T boundary

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The first known use of K-T boundary was in 1983

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Dictionary Entries Near K-T boundary

KT

K-T boundary

ktema es aei

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Cite this Entry

“K-T boundary.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/K-T%20boundary. Accessed 6 Jul. 2022.

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