The cardinal number immediately following eighty-eight and preceding ninety.(noun)
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Use "eighty-nine" in a sentence
"When home, in that first year alone, Obama hosted eighty-nine town-hall meetings throughout the state of Illinois."
"Reported attacks in Ingushetia rose from five in 2004 to 227 in 2008; those in Dagestan increased from twenty-nine to eighty-nine in the same period."
"Yet my college diploma says, “Given at Hempstead, New York, this thirty-first day of May, one thousand nine hundred AND eighty-nine.”"