Definition of rational
- a rational explanation
- rational behavior
- a rational root of an equation
human beings are rational creatures
insisted there was a rational explanation for the strange creaking noises and that there were no such things as ghosts
These example sentences are selected automatically from various online news sources to reflect current usage of the word 'rational.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.
First Known Use: 14th centurySee Words from the same year
: based on facts or reason and not on emotions or feelings
: having the ability to reason or think about things clearly
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