deviation

noun

de·​vi·​a·​tion ˌdē-vē-ˈā-shən How to pronounce deviation (audio)
: an act or instance of deviating: such as
a
navigation : deflection of the needle of a compass caused by local magnetic influences (as in a ship)
b
mathematics : the difference between a value in a frequency distribution and a fixed number (such as the mean)
c
: departure from an established ideology or party line
deviation from Communist orthodoxy
d
: noticeable or marked departure from accepted norms (see norm sense 2) of behavior
deviationist noun or adjective

Examples of deviation in a Sentence

There have been slight deviations in the satellite's orbit. Having juice instead of coffee was a deviation from his usual routine. The pattern's deviation from the norm is significant.
Recent Examples on the Web
Examples are automatically compiled from online sources to show current usage. Read More Opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback.
Existing models put to the test The combined data from all three radio telescopes revealed a deviation higher than five sigma—a very strong signal. Chris Young, Interesting Engineering, 14 Nov. 2025 In the meantime, there’s plenty to do by replaying the game and finding every possible deviation in jokes and dispatch mastery. Christopher Cruz, Rolling Stone, 13 Nov. 2025 There may be slight deviations from the podcast audio. Amanda Luberto, AZCentral.com, 12 Nov. 2025 Serving as a subtle deviation from her black outfit, the shoes were crafted from espresso brown velvet. Jaden Thompson, Footwear News, 10 Nov. 2025 See All Example Sentences for deviation

Word History

Etymology

see deviate entry 1

First Known Use

15th century, in the meaning defined above

Time Traveler
The first known use of deviation was in the 15th century

Browse Nearby Words

Cite this Entry

“Deviation.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/deviation. Accessed 17 Nov. 2025.

Kids Definition

deviation

noun
de·​vi·​a·​tion ˌdē-vē-ˈā-shən How to pronounce deviation (audio)
: an act or instance of deviating: as
a
: the difference found by subtracting some fixed number (as the arithmetic mean of a series of statistical data) from any item of the series
b
: noticeable difference from accepted standards (as of behavior or morals)

Medical Definition

deviation

noun
de·​vi·​a·​tion ˌdē-vē-ˈā-shən How to pronounce deviation (audio)
: an act or instance of diverging from an established way or in a new direction: as
a
: evolutionary differentiation involving interpolation of new stages in the ancestral pattern of morphogenesis
b
: noticeable or marked departure from accepted norms of behavior

More from Merriam-Webster on deviation

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