The ordinal form of the number sixty-one, describing a person or thing in position number 61 of a sequence.(noun)
One of sixty-one equal parts of a whole.(noun)
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Use "sixty-first" in a sentence
"That means that if Roger Maris or Mickey Mantle hit their sixty-first home run in the one hundred fifty-fifth game of the season, their name will have an asterisk in the record book."
"Ernie supposed that made some sense; his sixty-first birthday was approaching and no part of him seemed to move as fast as it used to."
"Thus passed from this world Quintus Lutatius Catulus, in the sixty-first year of his life: consul, pontiff, and fierce upholder of the prerogatives of the Senate."