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Synonyms

deviation

American  
[dee-vee-ey-shuhn] / ˌdi viˈeɪ ʃən /

noun

  1. the act of deviating.

  2. departure from a standard or norm.

  3. Statistics. the difference between one of a set of values and some fixed value, usually the mean of the set.

  4. Navigation. the error of a magnetic compass, as that of a ship, on a given heading as a result of local magnetism.

  5. Optics.

    1. Also called deflection.  the bending of rays of light away from a straight line.

    2. angle of deviation.

  6. departure or divergence from an established dogma or ideology, especially a Communist one.

deviation British  
/ ˌdiːvɪˈeɪʃən /

noun

  1. an act or result of deviating

  2. statistics the difference between an observed value in a series of such values and their arithmetic mean

  3. the error of a compass due to local magnetic disturbances

"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012
deviation Scientific  
/ dē′vē-ā′shən /

  1. The difference between one number in a set and the mean of the set.

Other Word Forms

  • deviative adjective
  • deviatory adjective
  • nondeviation noun

Etymology

Origin of deviation

First recorded in 1375–1425; late Middle English, from Middle French, from Medieval Latin dēviātiōn-, stem of dēviātiō; equivalent to deviate + -ion

Example Sentences

Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.

This represents a 55% price-to-earnings-growth discount relative to its megacap technology peers and places the stock one standard deviation below its 10-year average, Nowak wrote.

From MarketWatch • Mar. 30, 2026

“But when you sum them all up together, it’s actually quite a substantial deviation from that standard.”

From Barron's • Mar. 27, 2026

Just as “The Complex” deviates from his first two novels, “Family Planning” and “The Association of Small Bombs” Mahajan’s career trajectory is also a deviation from that of a traditional novelist.

From Los Angeles Times • Mar. 23, 2026

Last week's opening race in Australia saw a large deviation in start performance across the grid.

From BBC • Mar. 12, 2026

The boy adores these trips, both for the contents of the buildings and the deviation from his set routine.

From "The Night Circus" by Erin Morgenstern

Definitions and idiom definitions from Dictionary.com Unabridged, based on the Random House Unabridged Dictionary, © Random House, Inc. 2023

Idioms from The American Heritage® Idioms Dictionary copyright © 2002, 2001, 1995 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company.