[1] : The Collaborative International Dictionary of English v.0.48

keen \keen\ k=en, a. compar. keener k=en"~er;
   superl. keenest. oe. kene sharp, bold, as. c=ene bold;
   akin to d. koen, ohg. kuoni, g. k"uhn, osw. kyn, k"on,
   icel. kaenn, for koenn wise; perh. akin to e. ken, can to
   be able. root45.
   1. sharp; having a fine edge or point; as, a keen razor, or a
      razor with a keen edge.
      1913 webster

            a bow he bare and arwes arrows bright and kene.
                                                  --chaucer.
      1913 webster

            that my keen knife see not the wound it makes.
                                                  --shak.
      1913 webster

   2. acute of mind; sharp; penetrating; having or expressing
      mental acuteness; as, a man of keen understanding; a keen
      look; keen features.
      1913 webster

            to make our wits more keen.           --shak.
      1913 webster

            before the keen inquiry of her thought. --cowper.
      1913 webster

   3. bitter; piercing; acrimonious; cutting; stinging; severe;
      as, keen satire or sarcasm.
      1913 webster

            good father cardinal, cry thou amen
            to my keen curses.                    --shak.
      1913 webster

   4. piercing; penetrating; cutting; sharp; -- applied to cold,
      wind, etc.; as, a keen wind; the cold is very keen.
      1913 webster

            breasts the keen air, and carols as he goes.
                                                  --goldsmith.
      1913 webster

   5. eager; vehement; fierce; as, a keen appetite. "of full
      kene will." --piers plowman.
      1913 webster

            so keen and greedy to confound a man. --shak.
      1913 webster

   6. wonderful; delightful; marvelous; as, that would be keen.
      slang
      pjc

   note: keen is often used in the composition of words, most of
         which are of obvious signification; as, keen-edged,
         keen-eyed, keen-sighted, keen-witted, etc.

   syn: prompt; eager; ardent; sharp; acute; cutting;
        penetrating; biting; severe; sarcastic; satirical;
        piercing; shrewd.
        1913 webster
see also:
keener keenest 

[2] : The Collaborative International Dictionary of English v.0.48

keen \keen\, v. t.
   to sharpen; to make cold. r.
   1913 webster

         cold winter keens the brightening flood. --thomson.
   1913 webster

[3] : The Collaborative International Dictionary of English v.0.48

keen \keen\, n. ir. caoine.
   a prolonged wail for a deceased person. cf. coranach.
   ireland --froude.
   1913 webster
see also:
coranach 

[4] : The Collaborative International Dictionary of English v.0.48

keen \keen\, v. i.
   to wail as a keener does. ireland
   1913 webster

[5] : WordNet (r) 2.0

keen
     adj 1: having or demonstrating ability to recognize or draw fine
            distinctions; "an acute observer of politics and
            politicians"; "incisive comments"; "icy knifelike
            reasoning"; "as sharp and incisive as the stroke of a
            fang"; "penetrating insight"; "frequent penetrative
            observations" syn: acute, discriminating, incisive,
             knifelike, penetrating, penetrative, piercing,
             sharp
     2: intense or sharp; "suffered exquisite pain"; "felt exquisite
        pleasure" syn: exquisite
     3: very penetrating and clear and sharp in operation; "an
        incisive mind"; "a keen intelligence"; "of sharp and
        active intellect" syn: incisive, sharp
     4: very good; "he did a bully job"; "a neat sports car"; "had a
        great time at the party"; "you look simply smashing" syn:
         bang-up, bully, corking, cracking, dandy, great,
         groovy, neat, nifty, not badp, peachy, slap-up,
         swell, smashing
     5: as physically painful as if caused by a sharp instrument; "a
        cutting wind"; "keen winds"; "knifelike cold"; "piercing
        knifelike pains"; "piercing cold"; "piercing criticism";
        "a stabbing pain"; "lancinating pain" syn: cutting, knifelike,
         piercing, stabbing, lancinate, lancinating
     6: having a sharp cutting edge or point; "a keen blade"
     n : a funeral lament sung with loud wailing
     v : express grief verbally; "we lamented the death of the child"
         syn: lament
see also:
acute discriminating incisive knifelike penetrating penetrative 
piercing sharp exquisite bang-up bully 
corking cracking dandy great groovy 
neat nifty not badp peachy slap-up 
swell smashing cutting stabbing lancinate 
lancinating lament 

[6] : Moby Thesaurus II by Grady Ward, 1.0

490 moby thesaurus words for "keen":
   attic, ok, siberian, ablaze, absorbing, ace-high, acerb, acerbate,
   acerbic, acid, acidic, acidulent, acidulous, acrid, acrimonious,
   active, acute, adroit, afire, aggressive, agile, agog, alacritous,
   alert, algid, alive, all agog, animate, animated, anxious, apt,
   arctic, ardent, argute, asperous, astringent, astute, athirst,
   attentive, avid, awake, bad, bang-up, bark, bawl, bellow,
   below zero, bemoan, bewail, biting, bitter, bitterly cold, blare,
   blat, bleak, blubber, boiling over, bonzer, boom, boreal, boss,
   brainy, bray, breathe, breathless, bright, brilliant, brisk,
   brumal, buggy, bugs, bully, burning, bursting to, but good, buzz,
   cackle, canny, cant, caterwaul, caustic, chant, chirp, clever,
   cold, cold as charity, cold as death, cold as ice, cold as marble,
   coo, cool, cordial, corking, coronach, corroding, corrosive,
   crackerjack, crafty, creak, creaky, crisp, crow, cry, cunning,
   cutting, dandy, dead march, death knell, death song, deep,
   deep-felt, deepgoing, delicious, delirious, deplore, desirous,
   detailed, devoted, devoted to, dexterous, dirge, discerning,
   discriminating, discriminative, distinct, distressful, distressing,
   divine, dolorous tirade, double-edged, drastic, drawl, droll,
   drunk, ducky, dynamic, eager, ear-piercing, earnest, edged,
   elegize, elegy, enamored of, energetic, enterprising, enthusiastic,
   epicedium, escharotic, eulogy, excessive, excited, exclaim,
   excruciating, exorbitant, exquisite, extravagant, extreme,
   exuberant, fab, facetious, featheredged, febrile, fervent, fervid,
   fevered, feverish, fierce, fiery, fine, fine and dandy, fired,
   flaming, flushed, flute, fond of, forceful, forcible, forward,
   freezing, freezing cold, frigid, full of life, full of pep,
   funeral march, funeral oration, funeral song, funny, furious, gasp,
   gay, gear, gelid, gifted, give sorrow words, glacial, glorious,
   glowing, go-go, graveside oration, great, grieve, grievous, groan,
   groovy, growl, grunt, gung ho, harsh, heartfelt, hearty, heated,
   heavy, hibernal, hiemal, hiss, homefelt, hot, howl, howling,
   humorous, humorsome, hunky-dory, hyperborean, ice-cold,
   ice-encrusted, icelike, icy, immoderate, impassioned, impatient,
   impetuous, incisive, inclement, indelible, intelligent,
   intemperate, intense, intoxicated, irritating, itching, jam-up,
   jeremiad, jesting, jocose, jocular, joking, joky, joshing,
   just dandy, keen-edged, keen-witted, keening, kinetic, knell,
   knifelike, lament, lamentation, lilt, lively, living, lusty, marvy,
   mean, mettlesome, moan, monody, mordacious, mordant, mourn,
   muffled drums, mumble, murmur, mutter, neat, nifty, nimble,
   nimble-witted, nipping, nippy, no dumbbell, nobby, nose-tickling,
   not born yesterday, numbing, nutty, okay, on fire, on the,
   on the alert, on the ball, on the job, out of sight, outcry,
   outrageous, painful, pant, panting, passing bell, passionate,
   peachy, peachy-keen, penetrating, peppy, perceptive, percipient,
   perfervid, perspicacious, pervading, piercing, pinching, pipe,
   piping, piquant, plaint, planctus, poignant, pointed, profound,
   prompt, pungent, qui vive, quick, quick-thinking, quick-witted,
   rapier-like, raring to, raw, razor-edged, ready, ready and willing,
   red-hot, reedy, repine, requiem, rigorous, ripping, roar, robust,
   rough, rum, rumble, salt, salty, sarcastic, sardonic, scathing,
   scintillating, scorching, screak, screaky, scream, screech,
   screeching, screechy, scrumptious, searing, sensitive, set, severe,
   sharp, sharp-sighted, sharp-witted, sharpened, shrewd, shriek,
   shrieking, shrieky, shrill, sibilate, sigh, sing, sing the blues,
   skirl, skreigh, slap-up, sleepless, sleety, slushy, smacking,
   smart, smashing, snap, snappy, snarl, snort, sob, solid,
   something else, sorrow, sough, sour, spanking, sparkling, specific,
   spiffing, spiffy, spirited, splitting, sprightly, squall, squawk,
   squeak, squeaking, squeaky, squeal, stabbing, steaming, steamy,
   steel-trap, stinging, stone-cold, strenuous, strident, stringent,
   strong, stunning, subzero, supercooled, swell, take-charge,
   take-over, talented, tart, thin, thirsty, threnode, threnody,
   thunder, tirade, tough, trenchant, trumpet, twang, two-edged,
   ululant, ululate, ululation, unblinking, unconscionable,
   unmistakable, unmistaken, unnodding, unrestrained, unsleeping,
   unwinking, vehement, venomous, vibrant, vigorous, violent,
   virulent, vital, vitriolic, vivacious, vivid, wail, wail of woe,
   wailing, wakeful, warble, warm, weep, weep over, whimper,
   whimsical, whine, whining, whisper, whistle, whistling, wide-awake,
   winterbound, winterlike, wintery, wintry, wise, withering, witty,
   wizard, wrawl, yammer, yap, yawp, yell, yelp, yowl, zealous,
   zestful, zesty, zippy

Keen >> K Words
Keen, definition of term: Keen
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