The term grievance has different meanings. However, I will tell you the one that I am familiar with which is in employment practices or the workplace. In the workplace a grievance is like filing a complaint with your employer. It occurs when you feel that you have been mistreated or wronged in some phase of the terms and conditions of your employment. It is a way for the employee to let the employer know that they think something wrong happened and the employer to explain why it may have happened.