Ageism is stereotyping, prejudice, and discrimination against people based on their age; this is fostered by longstanding racism and classism. It is the third major type of discrimination and affects older adults in particular. With the elderly populations increasing rapidly worldwide, care for older adults is becoming a main healthcare-related issue of the 21st century. Ageism in healthcare or long-term care affects the feelings and rights of older adults and jeopardizes their health status. Nurses are crucial carers for older adults. Their values, views, and beliefs regarding older adults affect their care behavior. However, in Taiwan, no consensus has been reached on ageism, and the topic has not been sufficiently discussed or researched. Related studies have focused on examining the stereotypes and attitudes, but not care practices, of students or nurses toward older adults. This study analyzed the interactions between stereotypical, prejudicial, and discriminatory behavior and ageism, elucidating the defining attributes related to the concept and providing examples and evidence of ageism in action. This study may provide staff involved in elderly care with a better understanding of ageism while providing a useful reference for caregivers of older adults. This conceptual analysis may improve current nursing practices and lead to value future research on the topic.