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antidepressant an·ti·de·pres·sant (ān'tē-dĭ-prěs'ənt, ān'tī-)
A drug used to prevent or relieve mental depression.
Drugs that prevent or relieve the symptoms of depression. Various psychological disorders are treated with antidepressants.
Note: Although there are many antidepressant drugs now in use, the best known is Prozac®.