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thirty

American  
[thur-tee] / ˈθɜr ti /

noun

plural

thirties
  1. a cardinal number, 10 times 3.

  2. a symbol for this number, as 30 or XXX.

  3. a set of this many persons or things.

  4. Printing, Journalism. 30-dash.

  5. thirties, the numbers, years, degrees, or the like, from 30 through 39, as in referring to numbered streets, indicating the years of a lifetime or of a century, or referring to degrees of temperature.

    He works in the East Thirties. She must be in her thirties. The temperature was in the thirties yesterday.


adjective

  1. amounting to 30 in number.

thirty British  
/ ˈθɜːtɪ /

noun

  1. the cardinal number that is the product of ten and three See also number

  2. a numeral, 30, XXX, etc, representing this number

  3. (plural) the numbers 30–39, esp the 30th to the 39th year of a person's life or of a century

  4. the amount or quantity that is three times as big as ten

  5. something representing, represented by, or consisting of 30 units

"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

determiner

    1. amounting to thirty

      thirty trees

    2. ( as pronoun )

      thirty are broken

"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Usage

Spelling tips for 30 The word thirty (30) is hard to spell because it doesn’t simply combine the spelling of the base number (three) with the suffix -ty, as is done in other easy-to-remember spellings like sixty and seventy.  How to spell thirty: When three is combined with suffixes, it transforms from three (a cardinal number) to third (an ordinal number).Then, the d is dropped: thirteen (not thirdteen); thirty (not thirdty). Remember: there's no d in thirty.

Etymology

Origin of thirty

before 900; Middle English thritty, Old English thrītig, equivalent to thrī three + -tig -ty 1; cognate with Dutch dertig, German dreissig, Old Norse thrjātīu

Example Sentences

Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.

We’d choose a cozy spot—in the living room or out on the deck if the weather was warm—and all four of us would read quietly for thirty minutes.

From Literature

It was nearly thirty below when I crawled into the sleeping bag.

From Literature

Her sled weighed no more than thirty pounds, a beautiful racer barely two feet wide and six feet long.

From Literature

Well, now I had thirty minutes of uninterrupted time to work on my Essa project.

From Literature

And then thirty years later, they realized he was right.

From Literature