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rational - definition and synonyms


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adjective rational pronunciation in American English /ˈræʃ(ə)nəl/
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  1. 1
    based on sensible practical reasons instead of emotions
    There didn’t seem to be any rational explanation for his actions.
    Your choice was perfectly rational under the circumstances.
    a rational approach to the problem
  2. 2
    thinking about what you do in a calm way, and making sensible and intelligent decisions
    Let’s try to discuss this like rational human beings.
    Calm down and try to be rational.

derived word


 rational pronunciation in American English /ˌræʃəˈnæləti/ noun [uncountable]
I hope we can introduce some rationality into these debates.


a course of study which is much shorter than a university course and focuses on the skills you need for a job, especially computer-related skills

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an ancient Roman system of underfloor heating, used to heat houses with hot air; from the Latin 'hypocaustum'

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