Plural of antibody.
An immunoglobulin molecule that has a specific amino acid sequence by virtue of which it interacts only with the antigen that induced its synthesis in cells of the lymphoid series (especially plasma cells) or with antigen closely related to it. antibodies are classified according to their ode of action as agglutinins, bacteriolysins, haemolysins, opsonins, precipitins, etc. Any of a large variety of proteins normally present in the body or produced in response to an antigen which it neutralizes, thus producing an immune response. Antibodies are produced as a means of secondary defense against foreign agents entering the body. They consist of a protein and are structured and coded to react to a specific antigen. antibodies can either be produced by direct exposure to a new type of foreign agent (active immunity) or via passive immunity, such as when a mammal sibling receives antibodies via the milk from its mother.