The cardinal number immediately following fifty-seven and preceding fifty-nine.(noun)
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Use "fifty-eight" in a sentence
"It would in some ways make it easier to round up votes for cloture: You could tell a colleague that you had, say, fifty-eight votes and absolutely needed his or her vote to get to sixty."
"Maybe the magic number should decline slowly over a month, but no further than fifty-eight or fifty-seven votes."
"The historian Elizabeth Pleck has found fifty-eight diaries and autobiographies of free white people who were born before 1850 that recount instances of physical punishment."