oro-, orrho-

The study of serum, originally for the presence of antibodies but now also applied to the examination of serum for the presence of circulating antigens and, by extension, to study other body fluids for antibodies or antigens.

Inflammation of a serous membrane.

An in vitro test result indicating the presence, in serum, of immunologically active material: The outcome of a orrhoreaction is usually an antibody, but may be sometimes an antigen.

A thin, watery, or serous discharge.

1. The medicinal use of whey, either by ingestion or by bathing.
2. Treatment of a disease or infection with an injection of an animal or human serum containing antitoxins or a serum that contains specific antibodies; serum-therapy.