singlismnoun [ U ]
uk/ˈsɪŋ.ɡəl.ɪ.zəm//ˈsɪŋ.ɡəl.ɪ.zəm/unfair treatment of people who are single (= not married):
Singlism in the workplace might involve single people covering unpopular shifts for those married employees with parental responsibilities.