Ageism is unfair treatment of people because of their age, most often because they are old. A boss who will not hire you “because you’re too old,” or a joke that treats older people as stupid or useless, is ageism. The word was coined in 1969 by the American academic Robert N. Butler, from age + -ism, the same kind of ending as racism or sexism. It is a serious newspaper-and-classroom word, not slang. Though actually, some people now also use it for unfairness toward the young; the first and still most common meaning is unfairness toward older people. It names the habit or the system, not the simple fact of growing old.