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Definition of "thirty" []

  • The cardinal number equal to 3 × 10. (noun)
  • A decade or the numbers from 30 to 39: They settled down in their thirties. The temperature fell into the thirties. (noun)
  • The decade from 30 to 39 in a century. (noun)
  • An indication of the end of a news story, usually written 30. (noun)
  • Sports The second point that is scored by one side in tennis. (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 "thirty" in a sentence
  • "I remember when I first heard the term thirty-five years ago when we were attending a"
  • "At last, after what he called thirty years of slavery, he was able to resign his post of critic."
  • "The Richelieu Steamboat Company was {149} formed in 1845, and took its other title thirty years later, when it made its first great 'merger.'"