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nu·me·ro u·no

(nmə-rō nō, ny-)

n.
Slang

1. One that is first in rank, order, or importance.

2. One's own interests; oneself.

adj.

Number one.

[Spanish número uno or Italian numero uno, number one.]

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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