billion

→ cardinal number (pl. billions or (with numeral or quantifying word) same)
1. the number equivalent to the product of a thousand and a million; 1,000,000,000 or 109. • (Brit. dated) a million million (1,000,000,000,000 or 1012).
2. (billions) (informal) a very large number or amount.
– DERIVATIVES billionth ordinal number .
– ORIGIN C17: from Fr., from million, by substitution of the prefix bi- ‘two’ for the initial letters.

“billion cardinal number” The Concise Oxford English Dictionary. Ed. Catherine Soanes and Angus Stevenson. Oxford University Press, 2004. Oxford Reference Online. Oxford University Press. Canterbury University. 11 October 2006