Dictionary

rational

1rational

adjective ra·tio·nal \ˈrash-nəl, ˈra-shə-nəl\

: based on facts or reason and not on emotions or feelings

: having the ability to reason or think about things clearly

Full 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

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

Rhymes with RATIONAL

2rational

noun

Definition of RATIONAL

:  something rational; specifically :  rational number

First Known Use of RATIONAL

1606

rational

adjective ra·tio·nal \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\ adverb

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