billion

n. number equal to a thousand millions, 1 000 000 000 (in the USA and France); number equal to a million millions, 1 000 000 000 000 (in Britain)

Billion may mean:Numbers Either of two numbers (see long and short scales for more detail):1,000,000,000 (one thousand million; ; SI prefix giga) - increasingly common meaning in English-language usage1,000,000,000,000 (one million million; ; SI prefix tera) - increasingly rare meaning in English-language usage; standard meaning in many other languages
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n. trillion, number equaling one thousand billions, one million millions, one followed by 12 zeros

n. billion, trillion

(n.)
According to the French and American method of numeration, a thousand millions, or 1,000,000,000; according to the English method, a million millions, or 1,000,000,000,000. See Numeration.