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thirty

num. · n.
US //ˈθɝˌdi// UK //θˈɜːti// thir·ty
  1. 1 the number 30 (num.)
    A1 Beginner

    the number 30.

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

    Example

    There are thirty days in the month of September.

    Example

    The research team spent thirty days collecting samples from the remote site before returning to the laboratory for analysis.

  2. 2 the age of 30 (n.)
    A2 Elementary

    the age of thirty years old.

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

    Example

    She decided to change her career when she turned thirty.

    Example

    Many professionals experience a significant shift in their career goals as they approach thirty and seek greater stability.

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  1. 3 a 30-second advert (n.)
    C1 Advanced Technical

    a television or radio advertisement that lasts for thirty seconds.

    a commercial broadcast lasting exactly thirty seconds.

    Example

    The company paid a lot of money for a thirty during the big game.

    Example

    The marketing agency focused on producing a high-impact thirty that would capture the audience's attention during the prime-time broadcast.

  2. 4 a pack of 30 beers (n.)
    C2 Proficiency American English Slang Informal

    a large box containing thirty cans or bottles of beer.

    a pack or 'rack' containing thirty units of beer.

    Example

    He picked up a thirty on his way to the party.

    Example

    The students arrived at the beach house with a thirty of cheap lager, prepared for the weekend celebrations.

    • thirty pack
Origin

From Middle English thirty, metathetic alternant of Middle English thriti, þrittiȝ, from Old English þrītiġ (“thirty”), from Proto-Germanic *þrīz tigiwiz (“thirty”, literally “three tens”), equivalent to three + -ty. Cognate with Scots therty, tretty (“thirty”), West Frisian tritich (“thirty”), Dutch dertig (“thirty”), German dreißig (“thirty”).

Idioms1 entry

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