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adjective \ˈkēn\

Simple Definition of keen

  • : having or showing an ability to think clearly and to understand what is not obvious or simple about something

  • : very strong and sensitive : highly developed

  • : very excited about and interested in something

Source: Merriam-Webster's Learner's Dictionary

Full Definition of keen

  1. 1 a :  having a fine edge or point :  sharp b :  affecting one as if by cutting <keen sarcasm> c :  pungent to the sense <a keen scent>

  2. 2 a (1) :  showing a quick and ardent responsiveness :  enthusiastic <a keen swimmer> (2) :  eager <was keen to begin> b of emotion or feeling :  intense <the keen delight in the chase — F. W. Maitland>

  3. 3 a :  intellectually alert :  having or characteristic of a quick penetrating mind <a keen student> <a keen awareness of the problem>; also :  shrewdly astute b :  sharply contested <keen debate> c :  extremely sensitive in perception <keen eyes>

  4. 4 :  wonderful, excellent

keenly adverb
keenness play \ˈkēn-nəs\ noun
keen on
  1. :  very enthusiastic or excited about <wasn't keen on going>

Examples of keen in a sentence

  1. When you've been trying to remember something and you suddenly remember it, the mental pleasure is keen. —Ian Frazier, Atlantic, October 2004

  2. Indeed, tobacco processors were keen to promote variety even further by saturating and mixing the cut and spun leaf with a miscellany of spices… —Simon Schama, The Embarrassment of Riches, 1988

  3. But Mary wasn't keen on braving the Athens streets alone so Magnus went instead; Mary would do a museum in the morning. —John le Carré, A Perfect Spy, 1986

  4. That he took a keen interest in scientific navigation is indicated by his keeping a daybook or journal (which has not survived), and by making an honest effort to determine longitude. —Samuel Eliot Morison, The European Discovery of America, 1971

  5. The keen clear wind swept in on his left cheek, and as he bore on the helm so the Sophie answered, quicker and more nervous than he had expected. —Patrick O'Brian, Master and Commander, 1970

  6. Planting himself squarely before the two tall cowboys who were standing, he looked straight into their lean, bronzed faces. He spared a full moment for that keen cool gaze before he spoke. —Zane Grey, Desert Gold, 1913

  7. She's a very keen observer of the political world.

  8. <pilots with especially keen eyesight>

Origin of keen

Middle English kene brave, sharp, from Old English cēne brave; akin to Old High German kuoni brave

First Known Use: 13th century

Synonym Discussion of keen

sharp, keen, acute mean having or showing alert competence and clear understanding. sharp implies quick perception, clever resourcefulness, or sometimes questionable trickiness <sharp enough to spot a confidence game>. keen suggests quickness, enthusiasm, and a penetrating mind <a keen observer of the political scene>. acute implies a power to penetrate and may suggest subtlety and sharpness of discrimination <an acute sense of style>.

eager, avid, keen, anxious, athirst mean moved by a strong and urgent desire or interest. eager implies ardor and enthusiasm and sometimes impatience at delay or restraint <eager to get started>. avid adds to eager the implication of insatiability or greed <avid for new thrills>. keen suggests intensity of interest and quick responsiveness in action <keen on the latest fashions>. anxious emphasizes fear of frustration or failure or disappointment <anxious not to make a social blunder>. athirst stresses yearning but not necessarily readiness for action <athirst for adventure>.



noun \ˈkēn\

Definition of keen

  1. :  a lamentation for the dead uttered in a loud wailing voice or sometimes in a wordless cry

Examples of keen in a sentence

  1. <the loud keens of the widows were heard throughout the war-ravaged city>

Origin of keen

(see 1keen)

First Known Use: 1830



verb \ˈkēn\

Simple Definition of keen

  • : to make a loud and long cry of sorrow

Source: Merriam-Webster's Learner's Dictionary

Full Definition of keen

  1. intransitive verb
  2. 1 a :  to make a loud and long cry of sorrow :  to lament with a keen b :  to make a sound suggestive of a loud cry of sorrow <a keening siren>

  3. 2 :  to lament, mourn, or complain loudly

  4. transitive verb
  5. :  to utter with a loud wailing voice or wordless cry

keener noun

Examples of keen in a sentence

  1. mourners keening at a funeral

  2. <victims of the disaster have been keening for weeks about the slowness of governmental aid>

Origin of keen

Irish caoinim I lament, weep

First Known Use: 1845

KEEN Defined for Kids


adjective \ˈkēn\

Definition of keen for Students


  1. 1 :  having a fine edge or point :  sharp <a keen knife>

  2. 2 :  having or showing mental sharpness <a keen observation>

  3. 3 :  very sensitive (as in seeing, smelling, or hearing) <keen eyesight>

  4. 4 :  full of enthusiasm :  eager <… everybody was very keen to hear details of what had happened … — J. K. Rowling, Goblet of Fire>

  5. 5 :  seeming to cut or sting <a keen wind>

keenly adverb
keenness noun

Seen and Heard

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


tending to dismiss important matters

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