irrationality

noun

ir·​rationality "+ How to pronounce irrationality (audio)
Synonyms of irrationalitynext
1
: the quality or state of being irrational: such as
a
: lack of being endowed with reason
b
: lack of accordance with reason : unreasonableness, foolishness
2
: something that is irrational : absurdity
3
: inequality of dispersion of different colors in refraction spectra (as between crown and flint glass)

Word History

Etymology

Medieval Latin or New Latin irrationalitas, from Latin irrationalis irrational + -itas -ity

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Cite this Entry

“Irrationality.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/irrationality. Accessed 14 Dec. 2025.

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