Simple Definition of rational

from our Learner's Dictionary

rational

adjective

1
: based on facts or reason and not on emotions or feelings
a rational decision/choice
I'm sure there is a rational [=sensible, reasonable] explanation for his decision.
2
: having the ability to reason or think about things clearly
No rational [=sane] person would behave like that.
Humans are rational beings. [=are able to use reason when thinking about something]

Cite this Entry

“Rational.” Merriam-Webster.com Simple Definition, Merriam-Webster, https://www.merriam-webster.com/simple/rational. Accessed 15 Apr. 2026.

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