What is the condition of being protected against a particular disease known as?

The term that best describes the condition of being protected against a particular disease is "immunity." Immunity refers to the body's ability to recognize and fight off pathogens, such as viruses or bacteria, that can cause illness. It can be acquired through previous infections or immunizations, or it may be inherent due to genetic factors or natural antibody production.

While "immunization" and "vaccination" are related processes that work to stimulate an immune response and create immunity, they are not synonymous with the condition itself. Immunization is the process by which a person is made resistant to an infectious disease, often through vaccination, while vaccination specifically refers to the administration of a vaccine to provoke an immune response. "Resistance" can describe a broader concept of the body's ability to withstand infectious agents, but it doesn't specifically capture the protective state that immunity represents. Thus, "immunity" is the most accurate term to describe the protection against disease.