Definition of rational
(Entry 1 of 2)
1a
: 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
rational
nounDefinition of rational (Entry 2 of 2)
: something rational
specifically
: rational number
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MerriamWebster unabridged
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Time Traveler for rational
The first known use of rational was in the 14th century
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