irrationnel

irrational

adjective ee-rah-syo-NEL Rare

Usage Note

Irrationnel describes something that goes against reason or logic. The feminine form is irrationnelle and the adverb is irrationnellement. In mathematics, un nombre irrationnel refers to an irrational number (like π). The antonym is rationnel(le), and the noun form is irrationalité (f).

Examples

"Sa peur des araignées est totalement irrationnelle."

Natural Translation

His fear of spiders is completely irrational.

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