“Irrationality” in Japanese
Short answer
Irrationality in Japanese is “背理” (hairi). Full meaning: absurdity, irrationality.
Other ways to say “Irrationality” in Japanese
不道理
fudouri unreasonableness, absurdity, irrationality
悖理
hairi absurdity, irrationality
非常識
hijoushiki lack of common sense, thoughtlessness, senselessness, irrationality, absurdity
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