from The American Heritage® Dictionary of the English Language, 5th Edition.

  • abbreviation karat
  • noun The 11th letter of the modern English alphabet.
  • noun Any of the speech sounds represented by the letter k.
  • noun The 11th in a series.
  • noun Something shaped like the letter K.

from The Century Dictionary.

  • As an abbreviation: In electricity, of kathode (cathode, which see) and kathodic (cathodic).
  • In mathematics: The Lemoine point in geometry.
  • In mineralogy, the middle letter of the general symbol hkl, given to the face of a crystal in the system of Miller. See symbol, 7.
  • In phys.: The symbol usually employed for moment of inertia. The letter K is used by some writers as a symbol of electrostatic capacity, but C is now almost universally adopted for this quantity.
  • A symbol usually employed to designate magnetic susceptibility.
  • A symbol for absolute temperature.
  • The eleventh letter and eighth consonant of the English alphabet; the eleventh character also of the Phenician alphabet, from which it has come to us through the Latin and Greek.
  • In chem., the symbol for potassium (NL. kalium).
  • As an abbreviation: [lowercase] In meteorology, of cumulus (c being used for cirrus).
  • Of king, knight, etc.: as, K. G., Knight of the Garter.
  • Of
  • In math., k is generally a constant coefficient. It is also a unit vector perpendicular to i and j.
  • As a numeral in medieval use, 250.

from the GNU version of the Collaborative International Dictionary of English.

  • the eleventh letter of the English alphabet, is nonvocal consonant. The form and sound of the letter K are from the Latin, which used the letter but little except in the early period of the language. It came into the Latin from the Greek, which received it from a Phœnician source, the ultimate origin probably being Egyptian. Etymologically K is most nearly related to c, g, h (which see).

from Wiktionary, Creative Commons Attribution/Share-Alike License.

  • noun The eleventh letter of the basic modern Latin alphabet.
  • noun voiceless velar plosive.
  • noun The eleventh letter of the English alphabet.
  • noun computing A kilobyte (more formally KB or kB).
  • noun colloquial kilometre or kilometres.
  • noun colloquial thousand or thousands.
  • noun The SI measurement value of 1,000
  • abbreviation See K
  • abbreviation colloquial, text messaging, Internet slang Abbreviation of okay. (Also spelled 'kay.)
  • noun The eleventh letter of the English alphabet, called kay and written in the Latin script.
  • noun The first letter of callsigns allocated to American broadcast television and radio stations west of the Mississippi river.
  • noun The ordinal number eleventh, derived from this letter of the English alphabet, called kay and written in the Latin script.

from WordNet 3.0 Copyright 2006 by Princeton University. All rights reserved.

  • noun a unit of information equal to 1024 bytes
  • adjective denoting a quantity consisting of 1,000 items or units
  • noun a light soft silver-white metallic element of the alkali metal group; oxidizes rapidly in air and reacts violently with water; is abundant in nature in combined forms occurring in sea water and in carnallite and kainite and sylvite
  • noun a unit of information equal to 1000 bytes
  • noun the basic unit of thermodynamic temperature adopted under the Systeme International d'Unites
  • noun the cardinal number that is the product of 10 and 100
  • noun the 11th letter of the Roman alphabet
  • noun street names for ketamine


Sorry, no etymologies found.


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  • Any such forcing relation is consistent and monotone: for no sentence A and no k does k force both A and ¬A. if k ‰¤ k² and k forces

    Intuitionistic Logic Moschovakis, Joan 2007

  • N before g, the sound of ng ([n =]): sing, also n before k-- [n =] g, -- i [n =] k. bang song lank rang long bank sang strong sank hang thing tank wink cling sung sink swing lung think sing swung brink sting stung

    How to Teach Phonics Lida M. Williams

  • Sum {from k = 2 to ∞} 1/k² = Sum {from k = 1 to ∞} 1/k² - 1 = π²/6 - 1 en Español

    Yahoo! Answers: Latest Questions 2010

  • = 3 Sum {from t = 1 to ∞} 1/t² - 3 Sum {from k = 2 to ∞} 1/k² notice that

    Yahoo! Answers: Latest Questions 2010

  • Choose $k$ to be sufficiently large so that for every $t$ in the interval $1+f (k-1), ..., f (k) $ the above property is true. simple plainness 2010

  • = 3 Sum {from k = 2 to ∞} 1/(k-1) ² - 3 Sum {from k = 2 to ∞} 1/k² substitute t = k-1 in the first sum

    Yahoo! Answers: Latest Questions 2010

  • Choose $k$ to be sufficiently large so that for every $t$ in the interval $1+f (k-1), ..., f (k) $ the above property is true. simple plainness 2010

  • N k a N  m d 'i 2Nk k  m = • Right-hand side is independent of i • Exact solution for a = 1 and a = 2: d i − d' i EUD − EUDmax = (a − 1) (a − 1) d 'i EUDmax

    Recently Uploaded Slideshows 2009

  • Thus your code should put 1*1 + 2*2 + 3*3 + ... + 49*49 + 50*50 into total. for (k = 1, total = 0; k < = 50; k++) total + = k*k;

    Answerbag: Latest Questions in Question Categories 2008

  • This quadratic equation has two solutions for k: k_+ = 1 and k_ - = (1-p) / p (we will assume that p does not equal one half, i.e. someone has an advantage in the game.)

    ScienceBlogs Channel : Life Science 2008

  • A co-worker told me she once nearly quit her job because someone replied “k” to a request she made.

    “Sure” is the most infuriating way to say “yes” Jeremy Gordon 2018

  • And ketamine, often called Special K in its illicit form, has become a popular party drug.

    Bulky Cameras, Meet The Lens-less FlatCam Jon Hamilton 2019


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  • K means kilobytes. You can't have too much k in your code.

    June 28, 2007

  • K. Chemical element symbol for Potassium.

    December 16, 2007

  • the eleventh letter in the alphabet

    November 12, 2010

  • k

    is a shortening of OK

    which is itself a shortening of okay

    which is a shortening of okelydokely ok.. not really.

    but it's related to okiedokie

    okey dokey

    January 15, 2013

  • "“Alright”, “Yes”, and the much-hated “k” just got a visual redesign."

    hang on.. people didn't like k?

    June 23, 2013