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Added 7 October 2026

rational

/ˈɹæʃ(ə)nəl/ noun

Latin root: rationalis Wiktionary

noun Definition from WordNet 3.1, Princeton University. Pronunciation from Wiktionary, via Kaikki.org. More about rational at Wordnik → Where our words come from →

An integer or a fraction.

adjective

Consistent with or based on or using reason.
rational behavior
Of or associated with or requiring the use of the mind.
intellectual problems
Capable of being expressed as a quotient of integers.
rational numbers

Origin

From Old French rationel, rational, from Latin rationalis (“of or belonging to reason, rational, reasonable; having a ratio”), from ratio (“reason; calculation”).

From Wiktionary, via Kaikki.org (CC BY-SA)

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