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bil·lion

(bĭlyən)

1. The cardinal number equal to 10⁹.

2. Chiefly British The cardinal number equal to 10¹².

3. An indefinitely large number.

[French, a million million : blend of bi-, second power; see BI-¹ and MILLION.]

billion adj.

Indo-European & Semitic Roots Appendices

Thousands of entries in the dictionary include etymologies that trace their origins back to reconstructed proto-languages. You can obtain more information about these forms in our online appendices:

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Semitic Roots

The Indo-European appendix covers nearly half of the Indo-European roots that have left their mark on English words. A more complete treatment of Indo-European roots and the English words derived from them is available in our Dictionary of Indo-European Roots.

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