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dysthymic disorder

noun
  1. a psychiatric disorder characterized by generalized depression that lasts for at least a year
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
dysthymic disorder in Medicine

dysthymic disorder

n.
  1. A chronic disturbance of mood lasting at least two years in adults or one year in children, characterized by recurrent periods of mild depression and such symptoms as insomnia, tearfulness, and pessimism.
The American Heritage® Stedman's Medical Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Company. Published by Houghton Mifflin Company.