the antigen or antibody in question, so a titer of 1:32 may be below the cut-off for one test but above for another. Other examples A viral titer is the lowest concentration of a virus that still infects cells. To determine the titer, several dilutions are prepared, such as 10−1, 10−2, 10−3, ... 10−8. The titer of a fat is the temperature, in degrees Celsius, at which it solidifies. The higher the titer, the harder the fat. This titer is used in determining whether an animal fat is considered tallow (titer higher than 40 °C) or a grease (titer below 40 °C). See also Serology Titration W/v Mg% Virus quantification Viral titer References Chemical pathology Titration Immunology Immunologic tests