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

Keep scrolling for more

Learn More about K-T boundary

Time Traveler for K-T boundary

Time Traveler

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

See more words from the same year

Statistics for K-T boundary

Cite this Entry

“K-T boundary.” The Merriam-Webster.com Dictionary, Merriam-Webster Inc., https://www.merriam-webster.com/dictionary/K-T%20boundary?dom=translatable&src=syn. Accessed 17 January 2020.

Comments on K-T boundary

What made you want to look up K-T boundary? Please tell us where you read or heard it (including the quote, if possible).

WORD OF THE DAY

a plan in which a last survivor takes all

Get Word of the Day daily email!

Test Your Vocabulary

The Eponym Quiz

  • rubens painting
  • Which is the best synonym of bowdlerize?
Spell It

Can you spell these 10 commonly misspelled words?

TAKE THE QUIZ
Dictionary Devil

Test Your Knowledge - and learn some interesting things along the way.

TAKE THE QUIZ
Love words? Need even more definitions?

Subscribe to America's largest dictionary and get thousands more definitions and advanced search—ad free!