ageist

adj

1. Unfairly discriminatory against someone based on their age.

   “Upon hearing that his employer would soon require yearly physical examinations and vision screening, my father exclaimed that the policy was ageist.”

   “Even though she had succeeded in the phone interview, when the ageist employer learned that the candidate was only 18 years old, she became hesitant.”

   “Finally, the participants expressed an ageist and ableist view of romantic relationships as unsuitable for autistic people under the age of 18, thus explaining why this issue is not, or should not, be addressed as part of the curriculum. Alex, for example, thought it was important to engage autistic students with this subject only from age 19, as part of preparing them for independent living: […]”

noun

1. A person who behaves in an ageist manner.

   “He didn’t like to think of himself as an ageist, but he had to admit that he hadn’t considered the needs of some of the more elderly participants.”