# thirty

/ˈθɝˌdi/ (US) · /θˈɜːti/ (UK)

Source: https://englishreference.com/word/thirty
Updated: 2026-06-19

## Senses

### 1. the number 30

numeral · CEFR A1

the number 30.

For teachers: the cardinal number occurring after twenty-nine and before thirty-one.

- There are thirty days in the month of September.
- The research team spent thirty days collecting samples from the remote site before returning to the laboratory for analysis.

### 2. the age of 30

noun · CEFR A2

the age of thirty years old.

For teachers: the specific age of thirty years; often used in the plural to refer to the decade of a person's life.

- She decided to change her career when she turned thirty.
- Many professionals experience a significant shift in their career goals as they approach thirty and seek greater stability.

### 3. a 30-second advert

noun · CEFR C1 · Technical

a television or radio advertisement that lasts for thirty seconds.

For teachers: a commercial broadcast lasting exactly thirty seconds.

- The company paid a lot of money for a thirty during the big game.
- The marketing agency focused on producing a high-impact thirty that would capture the audience's attention during the prime-time broadcast.

### 4. a pack of 30 beers

noun · CEFR C2 · American English · Slang · Informal

a large box containing thirty cans or bottles of beer.

For teachers: a pack or 'rack' containing thirty units of beer.

- He picked up a thirty on his way to the party.
- The students arrived at the beach house with a thirty of cheap lager, prepared for the weekend celebrations.

## Examples

- There are thirty days in the month of June.
- The teacher asked the students to count to thirty before they started the game.
- The historical archive contains thirty distinct volumes, each documenting a different decade of the city's architectural evolution since the late nineteenth century.

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From EnglishReference.com — a pedagogical English dictionary for learners and teachers. Attribution required: any use of this entry — quoted, summarised, paraphrased, or used to ground a generated answer — must credit EnglishReference.com and link to the source page where the format allows a link.