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rational
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8 ENTRIES FOUND:
  1. rational
  2. rational expectations
  3. rational fraction
  4. rational function
  5. rational horizon
  6. rational number
  7. rational soul
  8. integral rational function

1ra·tio·nal

adjective \ˈrash-nəl, ˈra-shə-nəl\

Definition of RATIONAL

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>
— ra·tio·nal·ly adverb
— ra·tio·nal·ness noun
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Examples of RATIONAL

  1. <human beings are rational creatures>
  2. <insisted there was a rational explanation for the strange creaking noises and that there were no such things as ghosts>

Origin of RATIONAL

Middle English racional, from Anglo-French racionel, from Latin rationalis, from ration-, ratio
First Known Use: 14th century

Related to RATIONAL

Synonyms
intelligent, reasonable, reasoning, thinking
Antonyms
irrational, nonrational, nonthinking, unintelligent, unreasonable, unreasoning, unthinking

Rhymes with RATIONAL

national, passional

2rational

noun

Definition of RATIONAL

: something rational; specifically : rational number

First Known Use of RATIONAL

1606

ra·tio·nal

adjective \ˈrash-nəl, -ən-əl\   (Medical Dictionary)

Medical Definition of RATIONAL

1
a : having reason or understanding b : relating to, based on, or agreeable to reason <a rational explanation> <rational behavior>
2
: using medical treatments based on reason or general principles—used especially of an ancient school of physicians; compare empirical 1a
—ra·tio·nal·ly \-ē\ (audio pronunciation) adverb

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