Dysthymia
Depressed mood for most of the day, for more days than not for at least 2 years, accompanied by 2 or the following symptoms: poor appetite or overeating, insomnia or hypersomnia, low energy, low self-esteem, poor concentration, or feelings of hopelessness.
Please see DSM-5 for a full definition1.
 

References:
 
  1. American Psychiatric Association. Diagnostic and Statistical Manual of Mental Disorders, Fifth Edition (DSM-5), American Psychiatric Association, Arlington, VA 2013.
 
 
12/2014