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billion

numeral
BIL-yuhn/ˈbɪljən/

3 meanings of billion

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  1. 1
    thousand millionnumeral
    A cardinal number equal to a thousand million, written as 1 followed by nine zeros (10⁹).

    Engineers estimated the bridge project would cost close to a billion in public funds.

    The galaxy contains several hundred billion stars.

    UsageAfter a number it takes no -s: seven billion people (not incorrect: seven billions people). Use billions of for an unstated amount.

    Similarmilliard

    Note

    The short-scale value, now the everyday one in American, modern British and Australian English. The Devon and Exeter Gazette in 1921 printed £7,000,000,000 beside the words "seven billion pounds", a guard against the older million-million value.

  2. 2
    huge numbernumeralcolloquial
    An indefinitely large number, used loosely to mean a very great quantity rather than an exact count.

    She seemed to have a billion excuses ready for being late.

    After the storm there were a billion little repairs waiting around the house.

    UsageUsually a billion or billions of before a plural noun: a billion excuses. Best kept to conversation, since a report reader may take it literally.

    Note

    Pure exaggeration: nobody saying it has counted anything. It belongs with invented numbers like zillion and gazillion, which push the hyperbole further.

  3. 3
    million millionnumeraldated
    A million times a million: the number 1 followed by twelve zeros (10¹²), equal to a thousand milliard.

    Older British textbooks defined a billion as a million million, written with twelve zeros.

    n = 1,000,000,000,000, that is, = a billion, or the square of a million
    1778, Francis Maseres, “A Method of Finding, by the Help of Sir Isaac Newton's Binomial Theorem, a Near Value of the very Slowly Converging…

    UsageIn older texts, check the context: billion may mean a million million there, not a thousand million.

    Similartrillion

    Note

    The long-scale value is the one the word's make-up spells out: French bi- ("two") plus -illion, a million raised to the second power. Francis Maseres called it "the square of a million" in 1778. When Stephen Ladyman spoke in the House of Commons in 2000, he had to explain that he meant "a British billion."

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Origin

From French billion, from bi- ("two") plus -illion.

Checked 5 Nov 2026 · 1 fact

  • English billion comes from French billion, formed from bi- meaning two and -illion. en.wiktionary.org