Ageism is prejudice against a person because of how old he or she is.
The treating of a person or people, especially youth or seniors, differently from others based on assumptions, prejudices or/and stereotypes relating to their age.
Bias against older adults (typically those in their sixties or older, but other times even younger if not even before middle-age).
Bias, hatred, bigotry and prejudice against age differences in other people's relationships, whether romantic or platonic.
