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twen·ty

(twĕntē, twŭn-)

1. The cardinal number equal to 2 × 10.

2. twenties

a. A decade or the numbers from 20 to 29: The children are now in their twenties. The temperature dipped into the twenties.

b. often Twenties The decade from 20 to 29 in a century.

3. A twenty-dollar bill.

[Middle English, from Old English twēntig; see dwo- in the Appendix of Indo-European roots.]

twenty adj. & pron.

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:

Indo-European Roots

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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Indo-European & Semitic Roots Appendices