a technique for analyzing, and measuring the concentration of, antibodies, hormones, etc. in the body, used in diagnosing disease, detecting the presence of a tumor or drug, etc.
Origin of immunoassayimmuno- + assay
A laboratory technique that makes use of the binding between an antigen and its homologous antibody in order to identify and quantify the specific antigen or antibody in a sample.
immuno- + assay