SEROLOGY
serology
(noun) the branch of medical science that deals with serums; especially with blood serums and disease
Source: WordNet® 3.1
Etymology
Noun
serology (countable and uncountable, plural serologies)
The science that studies the blood serum, and especially the reaction between antigens and antibodies in serum.
The characteristics of the blood serum in a particular disease or organism.
(countable, informal) A blood test to detect the presence of, and often to measure the amount of, various components of the serum (such as electrolytes, antibodies, and antigens).
Source: Wiktionary