noun uni·son \ˈyü-nə-sən, -nə-zən\

Definition of unison

  1. 1 a :  identity in musical pitch; specifically :  the interval of a perfect prime b :  the state of being so tuned or sounded c :  the writing, playing, or singing of parts in a musical passage at the same pitch or in octaves

  2. 2 :  a harmonious agreement or union :  concord



in unison

  1. 1 :  in perfect agreement :  so as to harmonize exactly <a class reciting in unison>

  2. 2 :  at the same time :  simultaneously

Examples of unison in a sentence

  1. <the members of the committee are in unison on this point>

Did You Know?

This word usually appears in the phrase "in unison", which means "together, at the same time" or "at the same musical pitch". So an excited crowd responding to a speaker may shout in unison, and a group of demonstrators may chant in unison. The old church music called Gregorian chant was written to be sung in unison, with no harmonizing voices, and kindergarten kids always sing in unison (at least when they can all find the same pitch). In a similar way, an aerobics class moves in unison following the instructor, and a group or even a whole town may work in unison when everyone agrees on a common goal.

Origin and Etymology of unison

Middle English unisoun, from Middle French unisson, from Medieval Latin unisonus having the same sound, from Latin uni- + sonus sound — more at sound

First Known Use: 15th century

UNISON Defined for Kids


noun uni·son \ˈyü-nə-sən\

Definition of unison for Students

  1. :  the state of being tuned or sounded at the same pitch or at an octave

in unison

  1. 1 :  in exact agreement <They are in unison as to what to do next.>

  2. 2 :  at the same time <… they all stuck their tongues out in unison … — Louise Fitzhugh, Harriet the Spy>

Seen and Heard

What made you want to look up unison? Please tell us where you read or heard it (including the quote, if possible).


to strike by flicking the finger outward

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