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Definition of "ninety" []

  • The cardinal number equal to 9 × 10. (noun)
  • A decade or the numbers from 90 to 99: My grandparents are in their nineties. During the heat wave, the temperature stayed in the nineties. (noun)
  • The decade from 90 to 99 in a century. (noun)

American Heritage(R) Dictionary of the English Language, Fifth Edition. Copyright (c) 2011 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.

Use "ninety" in a sentence
  • "Gabriel was despatched to him with that short chapter of the Koran, which we call the ninety-fourth, beginning with the words"
  • "By the end of this term ninety souls were added to the flock."
  • "The angel Gabriel was despatched to him with that short chapter of the Koran, which we call the ninety - fourth, beginning with the words "Have we not gladdened thy breast?""