irrational
1ir·ra·tio·nal
adj \i-ˈra-sh(ə-)nəl, ˌi(r)-\Definition of IRRATIONAL
: not rational: as a (1) : not endowed with reason or understanding (2) : lacking usual or normal mental clarity or coherence b : not governed by or according to reason <irrational fears> c Greek & Latin prosody (1) of a syllable : having a quantity other than that required by the meter (2) of a foot : containing such a syllable d (1) : being an irrational number <an irrational root of an equation> (2) : having a numerical value that is an irrational number <a length that is irrational>
— ir·ra·tio·nal·i·ty \-ˌra-shə-ˈna-lə-tē\ noun
— ir·ra·tio·nal·ly \-ˈra-sh(ə-)nə-lē\ adverb
See Examples of IRRATIONAL
- He became irrational as the fever got worse.
- She had an irrational fear of cats.
Origin of IRRATIONAL
Middle English, from Latin irrationalis, from in- + rationalis rational
First Known Use: 14th century
Related to IRRATIONAL
Synonyms: fallacious, illegitimate, inconsequent, inconsequential, invalid, illogical, nonrational, unreasonable, unreasoning, unsound, weak
Related Words: eristic (also eristical), misleading, sophistic (or sophistical), specious; half-baked, ill-advised, misguided, unconsidered, unreasoned; inconsistent; absurd, asinine, foolish, meaningless, nonsensical, preposterous, reasonless, senseless, silly; Kafkaesque, odd, peculiar, strange, surreal, unusual, weird; insane, mad, nutty, wacky (also whacky); disordered, disorganized, rambling, random; unconvincing; inexplicable, unaccountable, unexplainable
Near Antonyms: commonsense, sane, sensible, sober, wise; enlightened, informed, just, justified, reasoned; ordered, organized; clear, cogent, compelling, convincing, credible, persuasive, plausible, satisfying, solid; certain, sure, true; confirmed, corroborated, demonstrated, established, substantiated, validated
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