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

sudden \sud"den\, a. oe. sodian, sodein, of. sodain, sudain, f.
   soudain, l. subitaneus, fr. subitus sudden, that has come
   unexpectedly, p. p. of subire to come on, to steal upon; sub
   under, secretly + ire to go. see issue, and cf.
   subitaneous.
   1. happening without previous notice or with very brief
      notice; coming unexpectedly, or without the common
      preparation; immediate; instant; speedy. "o sudden wo"
      --chaucer. "for fear of sudden death." --shak.
      1913 webster

            sudden fear troubleth thee.           --job xxii.
                                                  10.
      1913 webster

   2. hastly prepared or employed; quick; rapid.
      1913 webster

            never was such a sudden scholar made. --shak.
      1913 webster

            the apples of asphaltis, appearing goodly to the
            sudden eye.                           --milton.
      1913 webster

   3. hasty; violent; rash; precipitate. obs. --shak.
      1913 webster

   syn: unexpected; unusual; abrupt; unlooked-for.
        1913 webster -- sud"denly, adv. -- sud"denness,
        n.
        1913 webster
see also:
issue subitaneous sud"denly sud"denness 

[2] : WordNet (r) 2.0

suddenness
     n : the quality of happening with headlong haste or without
         warning syn: abruptness, precipitateness, precipitance,
          precipitancy
see also:
abruptness precipitateness precipitance precipitancy 

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

28 moby thesaurus words for "suddenness":
   abruptness, alacrity, expeditiousness, feverishness, furiousness,
   haste, hastiness, hurriedness, impatience, impetuosity,
   impetuousness, impulsiveness, inexpectation, overhastiness,
   precipitance, precipitancy, precipitateness, precipitation,
   precipitatousness, precipitousness, promptness, quickness,
   rashness, recklessness, speed, swiftness, unanticipation,
   unexpectedness

Suddenness >> S Words
Suddenness, definition of term: Suddenness
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