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 meat may have been stored in a refrigerator experiencing unsafe deviations in temperature. — Eva Flowe october 21, Charlotte Observer, 21 Oct. 2026

Detecting such deviations could help distinguish between competing explanations for inflation and reveal more about the universe’s earliest conditions. — Kaif Shaikh, Interesting Engineering, 20 Oct. 2026

The results suggested that people who strongly preferred flawless items had more elaborate ideas about what their ideal product was and were sensitive to even small deviations from those ideas. — Aprajita Gautam, The Conversation, 20 Oct. 2026

If the Riemann hypothesis holds, then mathematicians can guarantee that any deviations from the average given by the prime number theorem will always be small. — Quanta Magazine, 19 Oct. 2026

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

• ablation
• aeration
• bination
• carnation
• cassation
• castration
• causation
• centration
• cessation
• cetacean
• chelation
• citation

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