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rational

Syllabification: (ra·tion·al)
Pronunciation: /ˈraSHənl, ˈraSHnəl/
Translate rational | into French | into German | into Italian | into Spanish
Definition of rational

adjective

  • 1based on or in accordance with reason or logic:I’m sure there’s a perfectly rational explanation
  • (of a person) able to think clearly, sensibly, and logically:Andrea’s upset—she’s not being very rational
  • endowed with the capacity to reason:man is a rational being
  • 2 Mathematics (of a number, quantity, or expression) expressible, or containing quantities that are expressible, as a ratio of whole numbers. When expressed as a decimal, a rational number has a finite or recurring expansion.

noun

Mathematics
  • a rational number.

Derivatives

rationality

Pronunciation: /ˌraSHəˈnalətē/
noun

rationally

Pronunciation: /ˈraSHənl-ē, ˈraSHnəlē/
adverb

Origin:

late Middle English (in the sense 'having the ability to reason'): from Latin rationalis, from ratio(n-) 'reckoning, reason' (see ratio)

rational in other Oxford dictionaries

Definition of rational in the British & World English dictionary

Nearby words

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