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Synonyms

duo

1 American  
[doo-oh, dyoo-oh] / ˈdu oʊ, ˈdyu oʊ /

noun

plural

duos

  1. Music. duet.

  2. two persons commonly associated with each other; couple.

  3. two animals or objects of the same sort; two things ordinarily placed or found together; a pair.

    a duo of lovebirds.
duo- 2 American  

  1. a combining form meaning “two,” used in the formation of compound words.

    duologue.
duo 1 British  
/ ˈdjuːəʊ /

noun

  1. music

    1. a pair of performers

    2. another word for duet

  2. a pair of actors, entertainers, etc

  3. informal a pair of closely connected individuals

"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012
duo- 2 British  

combining form

  1. indicating two

    duotone
"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Usage

What does duo- mean? Duo- is a combining form used like a prefix meaning “two.” It is occasionally used in technical terms.Duo- comes from Greek dýo and Latin duo, both meaning “two.” In fact, English’s own word two is related to these roots! Learn more at our entry at two.

Etymology

Origin of duo1

1580–90; < Italian < Latin: two

Origin of duo-2

Combining form of Greek dýo, Latin duo two

Compare meaning

How does duo compare to similar and commonly confused words? Explore the most common comparisons:

Example Sentences

Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.

A slower and less sophisticated version of “Blow My Mind” came out in 2002, while “Sucker for Love” was written with Norwegian duo Röyksopp in sessions for their 2014 collaborative EP.

From The Wall Street Journal • Mar. 31, 2026

The duo also break down a consequential voting rights case in Watson v.

From Slate • Mar. 26, 2026

There, the duo shared time in the backcourt for an up-and-coming Cougars squad.

From Los Angeles Times • Mar. 23, 2026

Directed by filmmaking duo Phil Lord and Christopher Miller, the movie marks "Amazon MGM's first big hit" since the retail giant acquired the storied studio in 2021, Gross noted.

From Barron's • Mar. 22, 2026

Back when we were the dynamic duo of Jilly Bean and Jessa Jean, we spent hours playing in these woods.

From "Legendary Frybread Drive-In" by Cynthia Leitich Smith

Definitions and idiom definitions from Dictionary.com Unabridged, based on the Random House Unabridged Dictionary, © Random House, Inc. 2023

Idioms from The American Heritage® Idioms Dictionary copyright © 2002, 2001, 1995 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company.