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

compulsion \compul"sion\, n. l. compulsio. see compel.
   the act of compelling, or the state of being compelled; the
   act of driving or urging by force or by physical or moral
   constraint; subjection to force.
   1913 webster

         if reasons were as plentiful as blackberries, i would
         give no man a reason upon compulsion.    --shak.
   1913 webster

         with what compulsion and laborious flight
         we sunk thus low.                        --milton.

   syn: see constraint.
        1913 webster
see also:
compel constraint 

[2] : WordNet (r) 2.0

compulsion
     n 1: an urge to do or say something that might be better left
          undone or unsaid syn: irresistible impulse
     2: an irrational motive for performing trivial or repetitive
        actions against your will syn: obsession
     3: using force to cause something; "though pressed into rugby
        under compulsion i began to enjoy the game"; "they didn`t
        have to use coercion" syn: coercion
see also:
irresistible impulse obsession coercion 

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

153 moby thesaurus words for "compulsion":
   abstraction, abulia, alienation, amperage, anxiety,
   anxiety equivalent, anxiety state, apathy, armipotence, authority,
   beef, black power, brute force, catatonic stupor, charge, charisma,
   clout, coercion, cogence, cogency, complex, compulsoriness,
   constraint, dejection, depression, detachment, dint, drive,
   driving, driving force, duress, effect, effectiveness,
   effectuality, elation, emotionalism, energy, euphoria, exigency,
   fascination, fixation, fixed idea, flower power, folie du doute,
   force, force majeure, forcefulness, full blast, full force,
   hang-up, hypercathexis, hypochondria, hysteria, hysterics,
   idee fixe, impellent, impelling, impelling force, impetus, impulse,
   impulsion, incentive, incitement, indifference, influence,
   insensibility, irresistible force, irresistible impulse, lethargy,
   main force, main strength, mana, mandatedness, mandatoriness,
   mania, melancholia, mental distress, might, might and main,
   mightiness, moment, momentum, monomania, morbid drive,
   motive power, moxie, muscle power, necessariness, necessitation,
   necessitude, necessity, need, obligation, obligatoriness,
   obligement, obsession, obsessive compulsion,
   pathological indecisiveness, pinch, pizzazz, poop, possession,
   potence, potency, potentiality, power, power pack, power structure,
   power struggle, powerfulness, preoccupation, prepossession,
   prepotency, press, pressing, pressure, productiveness,
   productivity, propulsion, psychalgia, psychomotor disturbance,
   puissance, pull, punch, push, rash impulse, ruling passion, sinew,
   steam, strength, stress, strong arm, stupor, superiority,
   superpower, thrust, tic, twitching, unresponsiveness, urge,
   urgency, validity, vehemence, vigor, vim, violence, virility,
   virtue, virulence, vitality, wattage, weight, withdrawal

[4] : THE DEVIL'S DICTIONARY ((C)1911 Released April 15 1993)

compulsion, n.  the eloquence of power.

Compulsion >> C Words
Compulsion, definition of term: Compulsion
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