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Classic usage
Estimated CEFR level: C2 — Proficiency
Estimated from word frequency; not an official CEFR classification.
From Middle English quaterniǒun, from Late Latin quaterniō, from quaternī (“four each”) + -iō, from quater (“four times”). Doublet of kern. The mathematics sense was coined by Irish mathematician and astronomer William Rowan Hamilton in 1843.
four, 4, IV, tetrad, quatern, quaternary, quaternity, quartet, quadruplet, foursome, Little Joe
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Classic usage
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