twen·ty (twĕntē, twŭn-)
1. The cardinal number equal to 2 × 10.
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.]
twenty adj. & pron.
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