thirty

[thur-tee]

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

/ 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

determiner

1. 1. amounting to thirty

      thirty trees

   2. ( as pronoun )

      thirty are broken

Word History and Origins

Origin of thirty¹

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

Word History and Origins

Origin of thirty¹

Old English thrītig; see _three , _-ty ¹

Example Sentences

"We definitely understand this concern," a spokesperson for Wellcome Leap told the BBC, adding that they work with local teams in thirty countries.

From BBC

You couldn’t get away from them, they could park singles at number one by sheer will,” Kirk, who in his early thirties, said.

From Los Angeles Times

At the federal level alone, disaster recovery plays out across more than thirty agencies.

From Salon

Sunday is set to be cooler as a north-easterly breeze sets in, though temperatures will still be in the high twenties and low thirties for many.

From BBC

Temperatures across the UK will be in the high twenties to low thirties for most.

From BBC

When To Use

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.