noun, often capitalized, often attributive
\ ˈkā How to pronounce k (audio) \
plural k's or ks\ ˈkāz How to pronounce k (audio) \

Definition of k

 (Entry 1 of 4)

1a : the 11th letter of the English alphabet
b : a graphic representation of this letter
c : a speech counterpart of orthographic k
2 : a graphic device for reproducing the letter k
3 : one designated k especially as the 11th in order or class
4 : something shaped like the letter K
5 : a unit vector parallel to the z-axis
6 [kilo-] : thousand a salary of $24K
7 [kilo-] : a unit of computer storage capacity equal to 1024 bytes uses 350K of disk space
8 capitalized [struck] : strikeout

Definition of k (Entry 2 of 4)

1 karat
2 kindergarten
3 king
4 kitchen
5 knit
6 knot
7 koruna
8 kosher often enclosed in a circle
9 kyat

Definition of K (Entry 3 of 4)

1 Kelvin
2 kilometer



Definition of K (Entry 4 of 4)


Words Starting With K

Browse 4,954 words and phrases that start with the letter K, from Kaaba to kyte.

Examples of k in a Sentence

Noun There is one k in “book.” The word ends in k. She earned a salary of $30K. The program uses 350K of disk space. The pitcher had more than 10 Ks in his last game.

First Known Use of k


before the 12th century, in the meaning defined at sense 1a

History and Etymology for k


New Latin kalium

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Time Traveler for k

Time Traveler

The first known use of k was before the 12th century

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Dictionary Entries Near k




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Statistics for k

Last Updated

15 Apr 2022

Cite this Entry

“K.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/k. Accessed 27 May. 2022.

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More Definitions for k


noun, often capitalized
\ ˈkā How to pronounce k (audio) \
plural k's or ks\ ˈkāz \

Kids Definition of k

1 : the eleventh letter of the English alphabet
3 : kilobyte



Medical Definition of K

1 dissociation constant; ionization constant
2 [New Latin kalium] potassium
3 kelvin

More from Merriam-Webster on k

Nglish: Translation of k for Spanish Speakers


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