Final answer:
Overt actions designed to exclude or avoid certain groups are termed discrimination, stemming from stereotypes and prejudice. Discrimination can take various forms, like social exclusion, unjust housing practices, or biased employment. Historical instances, such as segregation and the discrimination faced by Mary Whiton Calkins, illustrate these points.
Step-by-step explanation:
Overt actions taken to exclude, avoid, or distance oneself from other groups is known as discrimination. Discrimination occurs when negative beliefs (stereotypes) and negative attitudes (prejudice) about a particular group lead to the mistreatment of individuals based on their membership in that group. This can manifest in various forms, such as excluding certain groups from social circles or societal functions, unfair housing practices, or biased hiring systems. An example of institutional discrimination is highlighted in the historical refusal to grant Mary Whiton Calkins a PhD solely based on her gender, despite her meeting all the necessary requirements. Furthermore, practices like segregation and the historical enactment of Jim Crow laws are indicative of overt discrimination based on race or ethnicity, with such discriminatory acts having a longstanding presence in U.S. history.