enkd, yes, it is at least impolite and imprecise to use definition 1 when there are people who actually fall under the medical definition around.The actual definition is supplied by the DSM-IV. The DSM-IV lists major depression, disthymia, and bipolar disorder as 3 different "kinds" of depression.
The definitions are as follows:
Major depression is:
Over the last 2 weeks five of the following features should be present of which one or more should be:
1. depressed mood most of the day nearly every day
2. loss of interest or pleasure in almost all activities most of the day nearly every dayand the remaining (the total to make at least five) from any of the following:
3. significant weight loss or gain (more than 5% change in 1 month) or an increase or decrease in appetite nearly every day
4. insomnia or hypersomnia nearly every day
5. psychomotor agitation or retardation nearly every day (observable by others, not merely subjective feelings of restlessness or being slowed down)
6. fatigue or loss of energy nearly every day
7. feelings of worthlessness or excessive or inappropriate guilt (which may be delusional) nearly every day (not merely self reproach about being sick)
8. diminished ability to think or concentrate, or indecisiveness, nearly every day (either by subjective account or observation of others)
9. recurrent thoughts of death (not just fear of dying), recurrent suicidal ideation without a specific plan or a suicide attempt or a specific plan for committing suicide.And the symptoms cause clinically significant distress or impairment in occupational or other important areas of functioning.
BUT:
It cannot be established that an organic factor initiated and maintained the disturbance
The disturbance is not a normal reaction to the death of a loved one (morbid preoccupation with worthlessness, suicidal ideation, marked functional impairment or psychomotor retardation, or prolonged duration suggest bereavement complicated by major depression).
At no time during the disturbance have there been delusions or hallucinations for as long as two weeks in the absence of prominent mood symptoms (i.e. before the mood symptoms developed or after they have remitted).
Not super imposed on schizophrenia, schizophreniform disorder, delusional disorder or psychotic disorder not superimposed on schizophrenia.
According to the DSM-IV, dysthymia is characterized by an overwhelming yet chronic state of depression, exhibited by a depressed mood for most of the days, for more days than not, for at least 2 years. (In children and adolescents, mood can be irritable and duration must be at least 1 year.) The person who suffers from this disorder must not have gone for more than 2 months without experiencing two or more of the following symptoms:
poor appetite or overeating
insomnia or hypersomnia
low energy or fatigue
low self-esteem
poor concentration or difficulty making decisions
feelings of hopelessnessIn addition, no Major Depressive Episode has been present during the first two years (or one year in children and adolescents) and there has never been a Manic Episode, a Mixed Episode, or a Hypomanic Episode, and criteria have never been met for Cyclothymic Disorder. Further, the symptoms cannot be due to the direct physiological effects of a the use or abuse of a substance such as alcohol, drugs or medication or a general medical condition. The symptoms must also cause significant distress or impairment in social, occupational, educational or other important areas of functioning.
Bipolar is too big to put here; to see it go to this blicky: blicky
Alex