ageism

This term describes a systemic bias where individuals are stereotyped or marginalized based on their age. While it frequently refers to discrimination against the elderly in workplace or healthcare settings, it also encompasses prejudice against younger people, such as the dismissal of a young professional's expertise due to their perceived lack of experience. As an uncountable noun, ageism does not have a plural form and cannot be counted with numbers. To refer to a specific instance of this behavior, one must use a partitive construction such as a case of ageism or an act of ageism.