What is the term for the clumping of antigens with antibodies or red blood cells of different types?

Agglutination is the term that describes the clumping of particles, such as antigens with antibodies or red blood cells of different types. This process occurs when an antibody binds to its specific antigen, resulting in the formation of a complex that causes the particles to stick together. In the context of blood types, for example, agglutination can occur when incompatible blood types are mixed, leading to potentially serious consequences in transfusions.

The concept of agglutination is crucial in various biological processes, including immune responses and diagnostic tests, where identifying the presence of specific antigens or antibodies is necessary.

The other terms presented carry different meanings. Aggregation generally refers to a grouping or clustering without the specific immune response implications of agglutination, coagulation pertains to the process of blood clotting, and hemolysis involves the breaking down of red blood cells, which is a separate process from the clumping of cells or antigens with antibodies. Thus, agglutination is the most precise term for the scenario described in the question.