Mental Health: The ability to think clearly and constructively. A person’s condition with regard to their psychological and emotional well-being.
There can be many reasons people become victims of poor mental health and it is a subject that can easily become misunderstood
In many workplaces a "mental health day" is where an employee does not come to work and takes a sick day for reasons other than physical illness. Some people may consider a mental health day to be when someone simply does not feel like coming in to work, but the most accurate use of this term is related to true mental illness rather than a desire to skip work. (Unfortunately, some workplaces can drive their employees to mental illness for various reasons and in many cases it's not always the employee that has a mental illness, but it could be the employer or a work colleague)