The ordinal form of the number sixty-four, describing a person or thing in position number 64 of a sequence.(noun)
One of sixty-four equal parts of a whole.(noun)
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Use "sixty-fourth" in a sentence
"By 1903 Ford had achieved a tolerance of only one sixty-fourth."
"And just in case the rest of the world was under the impression that Libya had quietly joined the modern global community, Gadhafi managed to dispel those notions once and for all in September 2009 at the sixty-fourth session of the UN General Assembly."
"The very next day was the sixty-fourth anniversary of the February 13, 1945, firebombing during which Allied aircraft destroyed the previously untouched city, considered by many to be the most beautiful in Europe, the baroque “Florence on the Elbe.”"