Treating one or more members of a specified group unfairly as compared with other people. What does the noun discrimination mean?The practice of treating someone or a particular group in society less fairly than others. Discrimination is the practice of treating one person or group of people less fairly or less well than other people or groups. Discrimination is an action or practice that excludes, disadvantages, or merely differentiates between individuals or groups of individuals Definition of discrimination noun in Oxford Advanced American Dictionary. Of a cook: Skilful in preparing dainties.