Define occasional: of or relating to a particular occasion; created for a particular occasion â occasional in a sentence of or relating to a particular occasion; created for a particular occasion; acting as the occasion or contributing cause of somethingâ¦
The list of types of Mental illness mentioned in various sources includes: 1  Depressive disorders. 2  Depression. 3  Dysthymic disorder. 4  Bipolar disorder. 5  Cyclothymic disorder. 6  Anxiety disorders. 7  Panic disorder. 8  Social phobia. 9  Specific phobias.
Approximately one fourth of adults in the United States have a mental illness, and nearly half will develop at least one mental illness during their lifetime (3--5). The most common mental illnesses in adults are anxiety and mood disorders (4).