unison

(n.) - If people speak or do something in unison, they say the same words at the same time or do the same thing at the same time.
*This word is used with the word in: in unison

• Synonyms: agreement, alliance, unity, at the same time
• Antonyms: discord, disagreement
• Etymoloy: 1574 Latin, from uni- meaning "one" + sonus meaning "sound"
• Example: When I say, “Class!” you reply, “Yes!” in unison.

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