- a test for diagnosing an infectious disease by detecting the presence of antibody in the blood, based on the fixing of a known quantity of complement to the antigen being tested and the specific antibody that combines with it. Abbreviation: CFT
- med a serological test for detecting the presence of a specific antibody or antigen, used in the diagnosis of syphilis, etc
- An immunological test for determining the presence of a particular antibody in which serum is treated in a manner that allows existing antibodies to accept and bind to a known amount of antigen. If binding occurs the presence of the antibody is verified and its concentration in the serum can be calculated based on the amount of antigen added to the system.