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

rational \ra"tional\, n.
   a rational being. --young.
   1913 webster

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

rational \ra"tional\ ra^sh"u^nal, a. l. rationalis: cf.
   f. rationnel. see ratio, reason, and cf. rationale.
   1. relating to the reason; not physical; mental.
      1913 webster

            moral philosophy was his chiefest end; for the
            rational, the natural, and mathematics . . . were
            but simple pastimes in comparison of the other.
                                                  --sir t.
                                                  north.
      1913 webster

   2. having reason, or the faculty of reasoning; endowed with
      reason or understanding; reasoning.
      1913 webster

            it is our glory and happiness to have a rational
            nature.                               --law.
      1913 webster

   3. agreeable to reason; not absurd, preposterous,
      extravagant, foolish, fanciful, or the like; wise;
      judicious; as, rational conduct; a rational man.
      1913 webster

   4. chem. expressing the type, structure, relations, and
      reactions of a compound; graphic; -- said of formulae. see
      under formula.
      1913 webster

   rational horizon. astron. see horizon, 2
      b .

   rational quantity alg., one that can be expressed without
      the use of a radical sign, or in exact parts of unity; --
      opposed to irrational or radical quantity.

   rational symptom med., one elicited by the statements of
      the patient himself and not as the result of a physical
      examination.
      1913 webster

   syn: sane; sound; intelligent; reasonable; sensible; wise;
        discreet; judicious.

   usage: rational, reasonable. rational has reference to
          reason as a faculty of the mind, and is opposed to
          irrational; as, a rational being, a rational state of
          mind, rational views, etc. in these cases the
          speculative reason is more particularly, referred to.
          reasonable has reference to the exercise of this
          faculty for practical purposes, and means, governed or
          directed by reason; as, reasonable desires or plans; a
          reasonable charge; a reasonable prospect of success.
          1913 webster

                what higher in her society thou find'st
                attractive, human, rational, love still.
                                                  --milton.
          1913 webster

                a law may be reasonable in itself, although a
                man does not allow it, or does not know the
                reason of the lawgivers.          --swift.
          1913 webster
see also:
ratio reason rationale formula rational horizon horizon 
rational quantity irrational radical quantity rational symptom rational 
reasonable 

[3] : WordNet (r) 2.0

rational
     adj 1: consistent with or based on or using reason; "rational
            behavior"; "a process of rational inference";
            "rational thought" ant: irrational
     2: of or associated with or requiring the use of the mind;
        "intellectual problems"; "the triumph of the rational over
        the animal side of man" syn: intellectual, noetic
     3: capable of being expressed as a quotient of integers;
        "rational numbers" ant: irrational
     4: having its source in or being guided by the intellect
        distinguished from experience or emotion; "a rational
        analysis"
see also:
irrational intellectual noetic 

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

140 moby thesaurus words for "rational":
   acceptable, admissible, algorismic, algorithmic, aliquot,
   all there, analytic, balanced, bright, calm, cardinal, cerebral,
   circumspect, clear-eyed, clearheaded, clearminded, cogent,
   commonsense, compos mentis, conceptive, conceptual, consequent,
   cool, coolheaded, credible, decimal, differential, digital,
   discriminating, discursive, down-to-earth, earthy, endopsychic,
   enlightened, even, everyday, exponential, figural, figurate,
   figurative, finite, fractional, hardheaded, healthy-minded,
   ideational, imaginary, impair, impossible, infinite, informed,
   integral, intellectual, intelligent, internal, irrational,
   judicious, just, justifiable, knowing, knowledgeable, legitimate,
   level-headed, levelheaded, logarithmic, logical, logometric, lucid,
   matter-of-fact, mental, mentally sound, negative, noetic,
   noological, normal, not so dumb, numeral, numerary, numerative,
   numeric, odd, of sound mind, ordinal, pair, philosophical, phrenic,
   plausible, positive, positivistic, possible, practical,
   practical-minded, pragmatic, prime, prudent, psychic, psychologic,
   radical, ratiocinative, ratiocinatory, real, realist, realistic,
   reasonable, reasoning, reciprocal, right, sane, sane-minded,
   scientific, scientistic, secular, sensible, sober, sober-minded,
   sophic, sound, sound-minded, sound-thinking, spiritual, stable,
   straight-thinking, strong-minded, subjective, submultiple, surd,
   thinking, together, transcendental, understanding, unideal,
   unidealistic, unromantic, unsentimental, well-argued,
   well-balanced, well-founded, well-grounded, wholesome, wise,
   worldly

[5] : The Free On-line Dictionary of Computing (27 SEP 03)

rational
     
        mathematics a fractional number n/d, where n and d are
        integers, n is the numerator and d is the denominator.  the
        set of all rational numbers is usually called q.
        computers do not usually deal with rational numbers but
        instead convert them to real numbers which are represented
        approximately in some cases as floating-point numbers.
        compare irrational.
     
     
see also:
real floating-point irrational 

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

rational, adj.  devoid of all delusions save those of observation,
experience and reflection.

Rational >> R Words
Rational, definition of term: Rational
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Rational Number >> R Words
Rational Number, definition of term: Rational Number
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