Term: immunohistochemistry: an assay that shows specific antigens in tissues by the use of markers that are either fluorescent dyes or enzymes (such as horseradish peroxidase)
Broader: assay: a quantitative or qualitative test of a substance (especially an ore or a drug) to determine its components; frequently used to test for the presence or concentration of infectious agents or antibodies etc. | Unrelated: fardel: a burden (figuratively in the form of a bundle)