April fool

from WordNet (r) 3.0 (2006)
April fool
    n 1: the butt of a prank played on April 1st
    2: a practical joke or trick played on the first day of April
    
from The Collaborative International Dictionary of English v.0.48
Fool \Fool\, n. [OE. fol, n. & adj., F. fol, fou, foolish, mad;
   a fool, prob. fr. L. follis a bellows, wind bag, an inflated
   ball; perh. akin to E. bellows. Cf. {Folly}, {Follicle}.]
   1. One destitute of reason, or of the common powers of
      understanding; an idiot; a natural.
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   2. A person deficient in intellect; one who acts absurdly, or
      pursues a course contrary to the dictates of wisdom; one
      without judgment; a simpleton; a dolt.
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            Extol not riches, then, the toil of fools. --Milton.
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            Experience keeps a dear school, but fools will learn
            in no other.                          --Franklin.
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   3. (Script.) One who acts contrary to moral and religious
      wisdom; a wicked person.
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            The fool hath said in his heart, There is no God.
                                                  --Ps. xiv. 1.
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   4. One who counterfeits folly; a professional jester or
      buffoon; a retainer formerly kept to make sport, dressed
      fantastically in motley, with ridiculous accouterments.
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            Can they think me . . . their fool or jester?
                                                  --Milton.
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   {April fool}, {Court fool}, etc. See under {April}, {Court},
      etc.

   {Fool's cap}, a cap or hood to which bells were usually
      attached, formerly worn by professional jesters.

   {Fool's errand}, an unreasonable, silly, profitless adventure
      or undertaking.

   {Fool's gold}, iron or copper pyrites, resembling gold in
      color.

   {Fool's paradise}, a name applied to a limbo (see under
      {Limbo}) popularly believed to be the region of vanity and
      nonsense. Hence, any foolish pleasure or condition of vain
      self-satistaction.

   {Fool's parsley} (Bot.), an annual umbelliferous plant
      ({Aethusa Cynapium}) resembling parsley, but nauseous and
      poisonous.

   {To make a fool of}, to render ridiculous; to outwit; to
      shame. [Colloq.]

   {To play the fool}, to act foolishly; to act the buffoon; to
      act a foolish part. "I have played the fool, and have
      erred exceedingly." --1 Sam. xxvi. 21.
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from The Collaborative International Dictionary of English v.0.48
April \A"pril\, n. [L. Aprilis. OE. also Averil, F. Avril, fr.
   L. Aprilis.]
   1. The fourth month of the year.
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   2. Fig.: With reference to April being the month in which
      vegetation begins to put forth, the variableness of its
      weather, etc.
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            The April's her eyes; it is love's spring. --Shak.
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   {April fool}, one who is sportively imposed upon by others on
      the first day of April.
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from The Devil's Dictionary (1881-1906)
APRIL FOOL, n.  The March fool with another month added to his folly.
    

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