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irrational

irrational

192 4.4
Not based on clear reason or thinking
  • adjective
  • /ɪˈræʃənl/
translation icon : irracional
  • I have an irrational fear of flying.
  • irrational belief
  • irrational fear
  • irrational thinking

I'm saying really give those irrational fears their their time.

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Examples

  • Now I have like an irrational fear of financial news.

  • But anyone can have irrational beliefs and fake science.

  • Those kind of really irrational feelings come to surface at that point.

  • Business travel often leads to irrational behaviour.

  • I knew that it was irrational and crazy to blame myself, but I did.

    Fiction book (1995)
  • I once had a client who had irrational fear of heights.

  • So there is something, I would say, wildly irrational about the whole system.

  • Human aspirations are so ludicrous and irrational.

  • As Benoit heard the keys disappear down the hall, an irrational fear overtook him.

    Fiction book (1990)
  • My friend has an irrational fear of spiders that prevents him from going outside.

Synonyms

preposterous
vsirrational
72 7.3

Very silly and unreasonable so it seems laughable

denotes lack of logical support without necessarily being ridiculous
illogical
vsirrational
43 4.8

Does not make sense or follow clear reasons

focuses on the absence of logical explanation rather than mere nonsensical form
unreasoning
vsirrational
2 7.5

Not based on reason or careful thought and often comes from strong feelings

is a broader lack of logical justification applying to ideas and actions
alogical
vsirrational
9.9

Not following clear or sensible reasoning

is about lacking justification in everyday thinking rather than formal logic

Antonyms

382 3.8

Based on clear thinking and facts rather than emotion

100 3.9

Able to think clearly and make good choices

Compounds

irrational number
  • Specialized
1 5.6

A number that cannot be written as a fraction, for example π or √2

A strong dislike of a person or group without good reason

A sudden strong wish to do something without a clear reason

A reason for doing something that is not logical or sensible

How Irrational

absurd
288 4.4
irrational
192 4.4
unreasonable
125 3.0

Surface Forms

irrational positive
irrationaler comparative
irrationalest superlative

Morphology

irrational = rational (transparent) = ir + rational

The adjective 'irrational' is formed by productive negation (ir- + rational); learners who know 'rational' will readily understand 'not rational' in the sense of lacking reason.

Etymology

Irrational comes from Latin parts ir- 'not' and ratio 'reason' or 'calculation', the same root you see in rational and ratio. So irrational means not guided by 'reason' or clear thinking.