deviation

deviation — noun

1. a situation or action in which someone or something moves away from what is usua

1.nounB2
Definition

a situation or action in which someone or something moves away from what is usual, expected, or socially accepted

Example

The teacher spotted a clear deviation from the dress code when Haruto arrived in costume.

collocation: deviation from [rule/code]

Any deviation from the recipe could ruin the texture of the cake.

Common collocations
  • deviation from
  • social deviation
  • behavioral deviation
  • a minor deviation
  • a clear deviation
Synonyms
  • departure

    more neutral and widely used; does not carry the same negative judgment as deviation

  • divergence

    implies moving in a different direction rather than breaking a rule; often used in opinion or path contexts

  • aberration

    stronger and more formal; suggests an abnormal or unacceptable departure from the norm

  • anomaly

    highlights something that stands out as unusual rather than a deliberate act of moving away

Antonyms
  • conformity

    the state of following accepted rules or standards

  • adherence

    sticking closely to a rule, plan, or standard

  • compliance

    obeying a rule or request, often in a formal or required context

Grammar Patterns

deviation from [norm/standard/rule]

a deviation — countable with article when referring to a specific instance

Usage Note

Frequently followed by the preposition 'from' to specify the norm or standard being departed from. The uncountable form describes the general concept, while the countable form highlights one specific instance.

Common Mistakes

There was a big deviation of the rules.
There was a big deviation from the rules.
the correct preposition is 'from', not 'of'.

2. in statistics, the distance between one data point and the average or expected n

2.nounB2
Definition

in statistics, the distance between one data point and the average or expected number in a set of measurements

Example

The standard deviation tells you how spread out the test scores are.

technical term: standard deviation

A large deviation from the average might indicate a mistake in the measurement.

preposition: deviation from [average]

Common collocations
  • standard deviation
  • mean deviation
  • deviation from the mean
  • a small deviation
  • a large deviation
Synonyms
  • variance

    a related but distinct statistical term; variance is the square of the standard deviation

  • difference

    general term for the gap between numbers; less precise than deviation in formal statistics

  • variation

    broader term describing spread within a dataset; covers both deviation and other forms of dispersion

Grammar Patterns

[amount] deviation — modified by a value or adjective

deviation from [expected value/mean]

Usage Note

Most commonly encountered in the fixed phrase 'standard deviation', which is a core concept in descriptive statistics. Can be followed by 'of' when giving a specific value (a deviation of 2.5).

Word family

Synonym discussion

Sense: noun/1

Deviation, departure, divergence, aberration, and anomaly all describe a move away from a standard, but they differ in judgment and scope. Deviation is the broadest and most neutral — it simply describes the act of being different from a norm, whether in behavior or statistics. Departure is slightly more neutral and flexible, often used for opinion, plan, or routine changes without negative overtones. Divergence implies branching off in a new direction, as in opinions or paths, rather than breaking a rule. Aberration carries a strong negative judgment, suggesting a serious and abnormal departure that is unacceptable. Anomaly highlights oddity rather than intentional departure — something that simply stands out as unusual. For example, a deviation from office dress code might be minor, while an aberration in someone's character suggests something deeply unusual.

departure ↗divergenceaberrationanomaly

Common collocations

Nouns

  • degree of deviation
  • amount of deviation
  • rate of deviation

Adverbs

Phrases

  • deviation from the norm
  • deviation from the standard

Prepositions

Etymology

LatinFrenchEnglish

Deviation comes from Latin deviare, meaning 'to turn aside from the road'. The prefix de- means 'away, off' and via means 'way, road'. The word entered English in the late 1300s with a literal meaning of turning off a path, then developed its abstract sense of departing from accepted behavior by the 1600s. The statistical meaning, referring to how far a data point is from the average, emerged in the late 1800s as the field of modern statistics took shape.