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halo effect

noun
  1. a predisposition to admire all of a person's actions, work, etc., because of an estimable quality or action in the past.
  2. Psychology. a potential inaccuracy in observation, as of a person, due to overgeneralization from a limited amount of evidence or the influence of preconceived beliefs or a priori hypotheses: The assumption that he is an authority on the subject is a halo effect of his Ivy League manner.
  3. any desirable side effect.

Origin of halo effect

First recorded in 1925–30
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018
British Dictionary definitions for halo effect

halo effect

noun
  1. See horns and halo effect
  2. the beneficial effect on sales of a company's range of products produced by the popularity or high profile of one particular product
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