n. 1. a. The act of deviating or turning aside. b. An instance of this: "We made so many deviations up and down lanes ... that I was quite tired, and very glad, when we saw Yarmouth" (Charles Dickens). 2. a. Divergence from an accepted idea, policy, or norm of behavior: "Freud, as the leader of a powerful new movement, could not bear much deviation from his own central ideas" (Joseph Epstein). b. An instance of this; an abnormality or departure from a norm: "Vice was a deviation from our nature" (Henry Fielding). 3. Deflection of a compass needle caused by local magnetic influence, especially on a ship. 4. Statistics The difference, especially the absolute difference, between one number in a set of data and the mean of that set of data. de′vi·ation·ism n. de′vi·ation·ist adj. & n. Synonyms: deviation, aberration, divergence These nouns mean a departure from what is prescribed or expected: tolerates no deviation from the rules; an act that represented an aberration from his usual behavior; a doctrine seen as a divergence from previous beliefs. |
The American Heritage® Dictionary of the English Language, Fifth Edition copyright ©2022 by HarperCollins Publishers. All rights reserved.