deviation

noun

de·​vi·​a·​tion ˌdē-vē-ˈā-shən 

: 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

deviationism

ˌdē-vē-ˈā-shə-ˌni-zəm 

noun

deviationist

ˌdē-vē-ˈā-sh(ə-)nist 

noun or adjective

Synonyms of deviation

• departure
• detour
• divergence
• deflection

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

The Ramona Community Planning Group on May 1 unanimously approved a minor deviation that allows changes to Spirit of Joy’s original major use permit for their church project at the site, which fell through in 2021. —Susan Gill Vardon, San Diego Union-Tribune, 31 Dec. 2025

Gloves, especially in fun colors and leather finishes, are statement pieces in addition to necessities, while earmuffs are a playful deviation from your go-to beanie. —Julia Guerra, InStyle, 31 Dec. 2025

This deviation is courtesy of the Pout Preserve Hydrating Peptide Lip Treatment — specifically the Strawberry Sorbet finish. —Averi Baudler, PEOPLE, 31 Dec. 2025

Takaichi angered China by giving a hypothetical example of such a situation, a deviation from former leaders’ strategic ambiguity. —Mari Yamaguchi, Los Angeles Times, 31 Dec. 2025

Word History

Etymology

see deviate entry 1

First Known Use

15th century, in the meaning defined above

Phrases Containing deviation

• mean deviation
• mean square deviation
• standard deviation

Rhymes for deviation

• abdication
• aberration
• abjuration
• abnegation
• abrogation
• acceptation
• acclamation
• acclimation
• accusation
• activation
• actuation
• acylation

Kids Definition

deviation

noun

de·​vi·​a·​tion ˌdē-vē-ˈā-shən 

: 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 

: 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