irrational

If you're a straight-A student and still you worry about failing all of your classes, you're being irrational. Your fears are not based on fact and not likely to come true.

Usually you use irrational to describe ideas and thoughts that are not based on reason, although emotions and behavior can be irrational too if they don't seem reasonable. Do you jump onto a chair and scream when you see a mouse? If so, you have an irrational fear of mice, or musophobia. If someone takes a swing at you for failing to say excuse me when you burp, both their anger and their actions could be called irrational.

Primary Meanings of irrational

1.
adj
not consistent with or using reason
2.
adjn
real but not expressible as the quotient of two integers
a real number that cannot be expressed as a rational number
Full Definitions of irrational
1

adj not consistent with or using reason

irrational fears”
irrational animals”
Synonyms:
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
Antonyms:
rational
consistent with or based on or using reason
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
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2

adj real but not expressible as the quotient of two integers

irrational numbers”
Antonyms:
rational
capable of being expressed as a quotient of integers

n a real number that cannot be expressed as a rational number

Synonyms:
irrational number
Types:
show 4 types...
hide 4 types...
transcendental number
an irrational number that is not algebraic
algebraic number
root of an algebraic equation with rational coefficients
pi
the ratio of the circumference to the diameter of a circle; approximately equal to 3.14159265358979323846...
e
the base of the natural system of logarithms; approximately equal to 2.718282...
Type of:
real, real number
any rational or irrational number

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