rational

Use the adjective rational to describe people or ideas that operate according to logic or reason. While your brother has an artistic temperament, you have a rational one.

Rational comes from the Latin word rationalis, meaning reasonable or logical. If you're rational, you do things based on logic, as opposed to impulse or whimsy. The original meaning in English was of something endowed with the ability to reason. Before we knew how smart some animals like dolphins are, writers liked to distinguish rational human minds from the supposedly irrational, instinctual minds of animals.

Primary Meanings of rational

1.
adj
consistent with or based on or using reason
2.
adjn
capable of being expressed as a quotient of integers
an integer or a fraction
Full Definitions of rational
1

adj consistent with or based on or using reason

rational behavior”
“a process of rational inference”
rational thought”
Synonyms:
logical
capable of or reflecting the capability for correct and valid reasoning
coherent, logical, lucid
capable of thinking and expressing yourself in a clear and consistent manner
demythologised, demythologized
having mythical elements removed
intelligent, reasoning, thinking
endowed with the capacity to reason
reasonable, sane
marked by sound judgment
reasonable, sensible
showing reason or sound judgment
sane
mentally healthy; free from mental disorder
Antonyms:
irrational
not consistent with or using reason
incoherent
without logical or meaningful connection
illogical, unlogical
lacking in correct logical relation
blind, unreasoning
not based on reason or evidence
reasonless
not endowed with the capacity to reason
nonrational
not based on reason
superstitious
showing ignorance of the laws of nature and faith in magic or chance
unreasonable
not reasonable; not showing good judgment
show more antonyms...

adj of or associated with or requiring the use of the mind

“the triumph of the rational over the animal side of man”
Synonyms:
intellectual, noetic
mental
involving the mind or an intellectual process

adj having its source in or being guided by the intellect (as distinguished from experience or emotion)

“a rational analysis”
Synonyms:
intellectual
appealing to or using the intellect
2

adj capable of being expressed as a quotient of integers

rational numbers”
Antonyms:
irrational
real but not expressible as the quotient of two integers

n an integer or a fraction

Synonyms:
rational number
Types:
show 7 types...
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fraction
the quotient of two rational numbers
fixed-point part, mantissa
the positive fractional part of the representation of a logarithm; in the expression log 643 = 2.808 the mantissa is .808
common fraction, simple fraction
the quotient of two integers
improper fraction
a fraction whose numerator is larger than the denominator
proper fraction
a fraction with a numerator smaller than the denominator
complex fraction, compound fraction
a fraction with fractions in the numerator or denominator
continued fraction
a fraction whose numerator is an integer and whose denominator is an integer plus a fraction whose numerator is an integer and whose denominator is an integer plus a fraction and so on
Type of:
real, real number
any rational or irrational number

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