Adjacent Words

Rational definitions

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Webster's 1828 Dictionary

RA'TIONAL, a. [L. rationalis.]
1. Having reason or the faculty of reasoning; endowed with reason; opposed to irrational; as, man is a rational being; brutes are not rational animals.
It is our glory and happiness to have a rational nature.
2. Agreeable to reason; opposed to absurd; as a rational conclusion or inference; rational conduct.
3. Agreeable to reason; not extravagant.
4. Acting in conformity to reason; wise; judicious; as a rational man.
RA'TIONAL, n. A rational being.

WordNet (r) 3.0 (2005)

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, rational, 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 (as distinguished from experience or emotion); "a rational analysis" n
1: an integer or a fraction [syn: rational number, rational]

Merriam Webster's

I. adjective Etymology: Middle English racional, from Anglo-French racionel, from Latin rationalis, from ration-, ratio Date: 14th century 1. a. having reason or understanding b. relating to, based on, or agreeable to reason ; reasonable <a rational explanation> <rational behavior> 2. involving only multiplication, division, addition, and subtraction and only a finite number of times 3. relating to, consisting of, or being one or more rational numbers <a rational root of an equation> • rationally adverb • rationalness noun II. noun Date: 1606 something rational; specifically rational number

Oxford Reference Dictionary

adj. 1 of or based on reasoning or reason. 2 sensible, sane, moderate; not foolish or absurd or extreme. 3 endowed with reason, reasoning. 4 rejecting what is unreasonable or cannot be tested by reason in religion or custom. 5 Math. (of a quantity or ratio) expressible as a ratio of whole numbers. Phrases and idioms: rational dress hist. a style of dress adopted by some women in the late nineteenth century, including bloomers or knickerbockers. rational horizon see HORIZON 1c. Derivatives: rationality n. rationally adv. Etymology: ME f. L rationalis (as RATION)

Webster's 1913 Dictionary

Rational Ra"tion*al, n. A rational being. --Young.

Webster's 1913 Dictionary

Rational Ra"tion*al, a. [L. rationalis: cf. F. rationnel. See Ratio, Reason, and cf. Rationale.] 1. Relating to reason; not physical; mental. 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. 2. Having reason, or the faculty of reasoning; endowed with reason or understanding; reasoning. It is our glory and happiness to have a rational nature. --Law. 3. Agreeable to reason; not absurd, preposterous, extravagant, foolish, fanciful, or the like; wise; judicious; as, rational conduct; a rational man. 4. (Chem.) Expressing the type, structure, relations, and reactions of a compound; graphic; -- said of formul[ae]. See under Formula. Rational horizon. (Astron.) See Horizon, 2 (b) . Rational quantity (Alg.), one that can be expressed without the use of a radical sign, or in extract 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.

Collin's Cobuild Dictionary

1. Rational decisions and thoughts are based on reason rather than on emotion. He's asking you to look at both sides of the case and come to a rational decision... ? irrational ADJ: usu ADJ n • rationally It can be very hard to think rationally when you're feeling so vulnerable and alone. ? irrationally ADV: usu ADV with v • rationality We live in an era of rationality. ? irrationality 2. A rational person is someone who is sensible and is able to make decisions based on intelligent thinking rather than on emotion. Did he come across as a sane rational person?... ? irrational ADJ

Soule's Dictionary of English Synonyms

a. 1. Intellectual, endowed with reason, reasoning. 2. Reasonable, just, right, equitable, moderate, fair, fit, proper, agreeable to reason, according to reason. 3. Judicious, sagacious, enlightened, sensible, discreet, wise, intelligent. 4. Sane, sound, sober, in one's right mind, in one's sober senses.

Moby Thesaurus

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