Two thirds; the amount or proportion corresponding to two out of three.(noun)
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Use "twothirds" in a sentence
"A network of Michigan hospitals that adopted the checklist slashed infections by twothirds, saving more than 1,500 lives and $200million in the first 18 months."
"Plato wrote of the "golden proportions," which dubbed the width of an ideal face an exact twothirds its length, a nose no longer than the distance between the eyes."
"Minorities are expected to account for more than twothirds of the net increase in households over the next decade, with the foreign born alone contributing at least one-third of the gains."