immunodiffusion im·mu·no·dif·fu·sion (ĭm'yə-nō-dĭ-fy&oomacr;'zhən, ĭ-my&oomacr;'-)
n.
A technique for studying reactions between antigens and antibodies by observing precipitates formed by the combination of specific antigens and antibodies that have diffused in a gel in which they have been separately placed.
| a white, crystalline, water-insoluble solid, C14H9Cl5, usually derived from chloral by reaction with chlorobenzene in the presence of fuming sulfuric acid: used as an insecticide and as a scabicide and pediculicide: agricultural use prohibited in the U.S. |
| the estimation of something as valueless (encountered mainly as an example of one of the longest words in the English language). |