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Svengali

American  
[sven-gah-lee, sfen-] / svɛnˈgɑ li, sfɛn- /

noun

  1. a person who completely dominates another, usually with selfish or sinister motives.

Svengali British  
/ svɛnˈɡɑːlɪ /

noun

  1. a person who controls another's mind, usually with sinister intentions

"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

Etymology

Origin of Svengali

First recorded in 1940–45; after the evil hypnotist of the same name in the novel Trilby (1894) by George Du Maurier

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.