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gender dysphoria

noun
  1. a psychological condition marked by significant emotional distress and impairment in life functioning, caused by a lack of congruence between gender identity and biological sex assigned at birth.
Also called gender identity disorder.

Usage note

Some transgender individuals and their advocates object to the use of the word "disorder" to describe this condition and therefore reject use of the variant term gender identity disorder. However, others feel that classifying it as a disorder may facilitate access to medical care related to the condition.
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018
British Dictionary definitions for gender dysphoria

gender dysphoria

noun
  1. a condition in which a person feels uncertainty or anxiety about his or her birth gender
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