irrational

noun

(mathematics) A real number that can not be expressed as the quotient of two integers, an irrational number.

adjective

Not rational; unfounded, nonsensical or wrong-headed.

(mathematics, arithmetic, number theory, not comparable) Of a real number, that cannot be written as the ratio of two integers.

Roots

inir- · Latin · not ratio-rat · Latin · reason, reckoning

Synonyms for irrational

illogicaladj unreasonableadj reasonlessadj unreasoningadj rationaladj insaneadj crackbrainedadj crazyadj senselessadj brainsickadj foolishadj

Synonyms & related words for irrational

Find synonyms, related words, and the definition of irrational — including illogical, unreasonable, reasonless, unreasoning, rational, insane. Dendril is a free visual thesaurus that shows them on an interactive map where stronger matches sit closer to the center — no signup, no ads.

Words related to irrational

Explore words related to irrational — words associated with it, words that go with it, and its nearest matches in meaning. Related words include irrationalize, irrationally, antirational, irrationality, unreasoned, illogically, unreasonableness, absurd. Click any word to make it the center of the map and keep exploring the web of connections.

Synonyms for irrational

Common synonyms for irrational include illogical, unreasonable, reasonless, unreasoning, rational, insane, crackbrained, crazy — words that share a close meaning. Hover or tap any word on the map for its definition and part of speech.

Where does irrational come from?

The word irrational breaks down into 2 roots of Latin origin: ir-, from Latin in (“not”); and -rat, from Latin ratio (“reason, reckoning”). Explore each root to see other English words built from the same source.