ninetieth

American  

[nahyn-tee-ith] / ˈnaɪn ti ɪθ /

adjective

1. next after the eighty-ninth; being the ordinal number for 90.

2. being one of 90 equal parts.

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noun

1. a ninetieth part, especially of one (1/90).

2. the ninetieth member of a series.

ninetieth British  

/ ˈnaɪntɪɪθ /

adjective

1. (usually prenominal)

   1. being the ordinal number of ninety in numbering or counting order, position, time, etc. Often written: 90th

   2. ( as noun )

      the ninetieth in succession

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noun

1. 1. one of 90 approximately equal parts of something

   2. ( as modifier )

      a ninetieth part

2. the fraction equal to one divided by 90 ( 1/ 90 )

Etymology

Origin of ninetieth

before 1100; Middle English nyntithe, Old English nigenteotha. See ninety, -eth ²

Example Sentences

Now, strangely, I draw breath Well past my ninetieth.

From New York Times • Jan. 9, 2023

Since 1989, a household at the tenth percentile is barely better off, while a household at the ninetieth percentile has almost one-third more income.

From Salon • Dec. 1, 2019

I told him I was enlisting to go with him on his ninetieth birthday parachute jump.

From New York Times • Dec. 2, 2018

In August, on Güler’s ninetieth birthday, a museum devoted to his legacy opened, at last, in Istanbul.

From The New Yorker • Oct. 27, 2018

"Lord Walder is well, my lady. He plans to take a new wife on his ninetieth name day, and has asked your lord father to honor the wedding with his presence."

From "A Game of Thrones" by George R.R. Martin