Source : Webster's Revised Unabridged Dictionary (1913)

Cool \Cool\, a. [Compar. {Cooler}; superl. {Coolest}.] [AS.
   c[=o]l; akin to D. koel, G. k["u]hl, OHG. chouli, Dan.
   k["o]lig, Sw. kylig, also to AS. calan to be cold, Icel.
   kala. See {Cold}, and cf. {Chill}.]
   1. Moderately cold; between warm and cold; lacking in warmth;
      producing or promoting coolness.

            Fanned with cool winds.               --Milton.

   2. Not ardent, warm, fond, or passionate; not hasty;
      deliberate; exercising self-control; self-possessed;
      dispassionate; indifferent; as, a cool lover; a cool
      debater.

            For a patriot, too cool.              --Goldsmith.

   3. Not retaining heat; light; as, a cool dress.

   4. Manifesting coldness or dislike; chilling; apathetic; as,
      a cool manner.

   5. Quietly impudent; negligent of propriety in matters of
      minor importance, either ignorantly or willfully;
      presuming and selfish; audacious; as, cool behavior.

            Its cool stare of familiarity was intolerable.
                                                  --Hawthorne.

   6. Applied facetiously, in a vague sense, to a sum of money,
      commonly as if to give emphasis to the largeness of the
      amount.

            He had lost a cool hundred.           --Fielding.

            Leaving a cool thousand to Mr. Matthew Pocket.
                                                  --Dickens.

   Syn: Calm; dispassionate; self-possessed; composed;
        repulsive; frigid; alienated; impudent.

Cool \Cool\, n.
   A moderate state of cold; coolness; -- said of the
   temperature of the air between hot and cold; as, the cool of
   the day; the cool of the morning or evening.

Cool \Cool\, v. t. [imp. & p. p. {Cooled}; p. pr. & vb. n.
   {Cooling}.]
   1. To make cool or cold; to reduce the temperature of; as,
      ice cools water.

            Send Lazarus, that he may dip the tip of his finger
            in water, and cool my tongue.         --Luke xvi.
                                                  24.

   2. To moderate the heat or excitement of; to allay, as
      passion of any kind; to calm; to moderate.

            We have reason to cool our raging motions, our
            carnal stings, our unbitted lusts.    --Shak.

   {To cool the heels}, to dance attendance; to wait, as for
      admission to a patron's house. [Colloq.] --Dryden.

Cool \Cool\, v. i.
   1. To become less hot; to lose heat.

            I saw a smith stand with his hammer, thus, the
            whilst his iron did on the anvil cool. --Shak.

   2. To lose the heat of excitement or passion; to become more
      moderate.

            I will not give myself liberty to think, lest I
            should cool.                          --Congreve.

Source : WordNet®

cool
     adj 1: neither warm or very cold; giving relief from heat; "a cool
            autumn day"; "a cool room"; "cool summer dresses";
            "cool drinks"; "a cool breeze" [ant: {warm}]
     2: marked by calm self-control (especially in trying
        circumstances); unemotional; "play it cool"; "keep cool";
        "stayed coolheaded in the crisis"; "the most nerveless
        winner in the history of the tournament" [syn: {coolheaded},
         {nerveless}]
     3: (color) inducing the impression of coolness; used especially
        of greens and blues and violets; "cool greens and blues
        and violets" [ant: {warm}]
     4: psychologically cool and unenthusiastic; unfriendly or
        unresponsive or showing dislike; "relations were cool and
        polite"; "a cool reception"; "cool to the idea of higher
        taxes" [ant: {warm}]
     5: used of a number or sum and meaning without exaggeration or
        qualification; "a cool million bucks"
     6: fashionable and attractive at the time; often skilled or
        socially adept; "he's a cool dude"; "that's cool"; "Mary's
        dress is really cool"; "it's not cool to arrive at a party
        too early"

cool
     n 1: the quality of being cool; "the cool of early morning"
     2: great coolness and composure under strain; "keep your cool"
        [syn: {aplomb}, {assuredness}, {poise}, {sang-froid}]

cool
     v 1: make cool or cooler; "Chill the food" [syn: {chill}, {cool
          down}] [ant: {heat}]
     2: loose heat; "The air cooled considerably after the
        thunderstorm" [syn: {chill}, {cool down}] [ant: {heat}]
     3: lose intensity; "His enthusiasm cooled considerably" [syn: {cool
        off}, {cool down}]

Source : Free On-Line Dictionary of Computing

COOL
     
        1. {Concurrent Object-Oriented Language}.
     
        2. CLIPS Object-Oriented Language?
     
        3. A C++ class library developed at {Texas Instruments}.  COOL
        contains a set of containers like Vectors, List, Hash_Table,
        etc.  It uses a shallow hierarchy with no common base class.
        The functionality is close to Common Lisp data structures
        (like libg++).  The template syntax is very close to Cfront3.x
        and g++2.x.  Can build shared libraries on Suns.
     
        JCOOL's main difference from COOL and GECOOL is that it uses
        real C++ templates instead of a similar syntax that is
        preprocessed by a special 'cpp' distributed with COOL and
        GECOOL.
     
        {(ftp://csc.ti.com/pub/COOL.tar.Z)}.
     
        GECOOL, JCOOL: {(ftp://cs.utexas.edu/pub/COOL/)}.
     
        E-mail: Van-Duc Nguyen 
     
        (1992-08-05)

CooL
     
         Combined object-oriented Language.
     
        An {object-oriented} language from the {ITHACA} {Esprit}
        project, which combines {C}-based languages with {database}
        technology.
     
        (1995-03-15)