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stack

n. · v.
US //ˈstæk// UK //stˈæk// stack
  1. 1 a pile (n.)
    B1 Intermediate

    a neat pile of objects, usually placed one on top of another.

    an orderly pile or heap of items, typically arranged vertically.

    Example

    He left a tall stack of newspapers on the kitchen table.

    Example

    A precarious stack of dusty journals occupied the corner of the office, threatening to topple at the slightest vibration.
  2. 2 a large amount (n.)
    B2 Upper Intermediate Informal

    a large quantity of something.

    a significant or large amount of something; often used in the plural.

    Example

    Don't worry about the cost; I've got stacks of money in my savings account.

    Example

    The researchers spent the weekend reviewing stacks of data before the final presentation on Monday morning.
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  1. 3 a chimney (n.)
    B2 Upper Intermediate

    a tall vertical pipe or chimney that lets out smoke or steam.

    a tall chimney or vertical exhaust pipe, especially on a factory, ship, or locomotive.

    Example

    Thick black smoke poured from the factory stack into the grey sky.

    Example

    The industrial landscape was dominated by massive concrete stacks that vented steam into the cold morning air.
  2. 4 library shelves (n.)
    C1 Advanced Academic

    the area in a library where many rows of books are kept.

    the main storage area of a library, consisting of numerous rows of bookshelves.

    Example

    I spent the afternoon wandering through the library stacks looking for a rare history book.

    Example

    Access to the closed stacks is restricted to faculty members and graduate students conducting primary research.
  3. 5 computing data structure (n.)
    C1 Advanced Technical Computing

    a way of storing computer data where the last item put in is the first one taken out.

    a last-in, first-out (LIFO) data structure used in programming for temporary storage and task management.

    Example

    The program crashed because the stack was full of too many temporary files.

    Example

    The developer implemented a stack to manage the undo history, ensuring the most recent action was always the first to be reversed.
    • LIFO
  4. 6 to cheat or manipulate (v.)
    B2 Upper Intermediate

    to arrange something, like a deck of cards, in a dishonest way to get an advantage.

    to manipulate the order of something, such as a deck of cards or a committee, to ensure a specific outcome.

    Example

    It felt like the odds were stacked against us from the very beginning.

    Example

    The opposition accused the governor of stacking the committee with his own supporters to guarantee the bill's passage.

    Usage

    Commonly used in the passive voice as 'the odds are stacked against someone'.

    Teacher's tip

    Explain the idiom 'to stack the deck' as a metaphor for creating an unfair situation.
Origin

From Middle English stack, stacke, stakke, stak, from Old Norse stakkr (“a barn; haystack; heap; pile”), from Proto-Germanic *stakkaz (“a barn; rick; haystack”). The data structure sense is a calque of Dutch stapel, introduced by Edsger W. Dijkstra. Cognate with Icelandic stakkur (“stack”), Swedish stack (“stack”), Danish stak (“stack”), Norwegian stakk (“stack”). Related to stake and sauna.

Idioms2 entries

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