[ eyl-yuh-nist, ey-lee-uh- ]
/ ˌeɪl yə nɪst, ˌeɪ li ə- /


(formerly) a doctor specializing in the treatment of mental illness.
an expert witness in a sanity trial.


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Origin of alienist

1860–65; alien(ation) + -ist; compare French aliéniste in same sense Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2020

Example sentences from the Web for alienist

British Dictionary definitions for alienist

/ (ˈeɪljənɪst, ˈeɪlɪə-) /


US a psychiatrist who specializes in the legal aspects of mental illness
obsolete a person who practises alienism
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

Medical definitions for alienist

[ ālyə-nĭst, ālē-ə- ]


A physician accepted by a court of law as an expert on the mental competence of principals or witnesses.
The American Heritage® Stedman's Medical Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Company. Published by Houghton Mifflin Company.