The ordinal form of the number eighty-four, describing a person or thing in position number 84 of a sequence.(noun)
One of eighty-four equal parts of a whole.(noun)
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Use "eighty-fourth" in a sentence
"At the eighty-fourth minute, Mehdi Mahdavikia decisively blasted a shot to the right corner of the net, past the diving American goalie."
"M. Gillenormand had, at that time, fully completed his eighty-fourth year."
"SINCE BOBBY JINDAL, a traditional Catholic and sometime New Oxford Review contributor, today became the eighty-fourth Governor of Louisiana sixty-first of the republican era, we decided to share with you the interesting development regarding the Louisiana state flag."