The ordinal form of the number forty-five, describing a person or thing in position number 45 of a sequence.(noun)
One of forty-five equal parts of a whole.(noun)
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Use "forty-fifth" in a sentence
"Mubarak's announcement only adds more pressure to the opening night of Spider-Man, which was just postponed for the forty-fifth time, following technical problems that caused some of the actors' heads to accidentally explode onto the preview audience."
"I'm in my forty-fifth year and, to be honest, I've never been a glamorous woman."
""People will call me on the forty-fifth day and say, 'I'm sending the check right now please don't charge the late fee!'" she says."