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duo-

pref.

Two: duopsony.

[Latin, from duo, two; see dwo- in the Appendix of Indo-European roots.]

du·o

(dō, dyō)

n. pl. du·os

1. Music A duet, especially two performers singing or playing together.

2. Two people or two things in close association: a duo of negotiators.

[Italian, from Latin, two; see dwo- in the Appendix of Indo-European roots.]

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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