rational

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adjective

1. Able to reason validly: analytic, analytical, logical, ratiocinative. See reason/unreason.
2. Possessing, proceeding from, or exhibiting good judgment and prudence: balanced, commonsensible, commonsensical, judicious, levelheaded, prudent, reasonable, sagacious, sage, sane, sapient, sensible, sound², well-founded, well-grounded, wise¹. See reason/unreason, sane/insane.
3. Mentally healthy: compos mentis, lucid, sane. Idioms: all there, in one's right mind, of sound mind. See sane/insane.
4. Consistent with reason and intellect: consequent, intelligent, logical, reasonable. See reason/unreason.

adj

Definition: realistic; of sound mind
Antonyms: illogical, irrational, ridiculous, unrealistic, unreasonable, unsound

Positive term used to commend beliefs, actions, processes as appropriate. In the case of beliefs this means likely to be true, or at least likely to be true from within the subject's perspective. Cognitive processes are rational insofar as they are reliable, and actions rational at least insofar as they provide likely means to an agent's ends. Further constraints on rational action, such as the ends themselves being rational, are of less certain meaning. See also rationality.

A cynical view of the world by Ambrose Bierce

adj.

Devoid of all delusions save those of observation, experience and reflection.

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Based upon reason.

• r. deductive diagnosis — a diagnosis based on rationalization of the signs with pathological and epidemiological principles, as distinct from empirical diagnosis.

For a list of words related to rational, see:

• Logic - rational: (adj) having reason; capable of reasoning
• Moderate, Sane, Conservative, or Old-Fashioned
• Intelligent, Informed, Clever, or Articulate
• Reason and Rationale - rational: (adj) conforming to reason

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See words rhyming with "rational."

  See crossword solutions for the clue Rational.

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Dansk (Danish)
adj. - rationel, fornuftig, fornuftsbetonet

Nederlands (Dutch)
rationeel, redelijk, verstandelijk, rationeel getal

Français (French)
adj. - rationnel, sensé, logique, objectif
n. - (Math) nombre rationnel

Deutsch (German)
adj. - rational, vernunftbegabt
n. - rationale Zahl

Ελληνική (Greek)
adj. - έλλογος, εύλογος, λογικός, ορθολογικός
n. - ρητός αριθμός (rational number)

Italiano (Italian)
razionale, ragionevole

Português (Portuguese)
adj. - racional
n. - racional (Mat., Filos.)

Русский (Russian)
разумный, рациональный

Español (Spanish)
adj. - racional, razonable
n. - racional

Svenska (Swedish)
adj. - rationell, förnuftig
n. - rationell storhet (mat)

中文（简体）(Chinese (Simplified))
理性的, 推理的, 合理的

中文（繁體）(Chinese (Traditional))
adj. - 理性的, 推理的, 合理的

한국어 (Korean)
adj. - 이성적인, 분별 있는, 합리적인

日本語 (Japanese)
adj. - 理性的な, 道理をわきまえた, 合理的な, 論理的な, 有理の

العربيه (Arabic)
‏(صفه) معقول, منطقي (الاسم) عاقل‏

עברית (Hebrew)
adj. - ‮שכלתני, רציונלי, נבון, שכלי, סביר, ממושכל, הגיוני‬

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