n. pl. tri·os
a. A composition for three voices or three instruments.
b. A group of three singers or three instrumentalists.
c. The middle, contrasting section of a minuet, scherzo, march, or various other forms.
2. A group of three.
[French, composition for three voices, from Italian : tri-, three (from Latin; see trei- in the Appendix of Indo-European roots) + (du)o, duet; see DUO.]
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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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