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theoretician

American  
[thee-er-i-tish-uhn, theer-i-] / ˌθi ər ɪˈtɪʃ ən, ˌθɪər ɪ- /

noun

  1. a person who deals with or is expert in the theoretical side of a subject.

    a military theoretician.
theoretician British  
/ ˌθɪərɪˈtɪʃən /

noun

  1. a student or user of the theory rather than the practical aspects of a subject

"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 theoretician

First recorded in 1885–90; theoretic(s) + -ian

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.