immunology

The term 'immunology' is a modern scientific compound formed in the late 19th century. Its first element, 'immuno-', derives from the Latin immunis, which originally meant "exempt from public service" or "free from a burden" (from in- "not" + munia "duties"). This sense of exemption was metaphorically applied in medicine to describe protection from disease. The second element, '-logy', comes from the Greek -logia, a suffix denoting a discourse, theory, or science, itself from logos meaning "word" or "reason". Thus, the literal construction "the study of (that which provides) exemption" perfectly captures the field's focus on understanding the biological mechanisms that grant freedom from infection.

Structure: immuno (immune) + logy (study of) - immuno: From Latin immunis (exempt from public service, free from a burden). In this word, it functions as a combining form meaning "immune" or "immunity". - logy: From Greek -logia (denoting a branch of knowledge or science). In this word, it functions as a suffix meaning "the study of".