/i luy"zeuh, -seuh/ , n.
1. Med. a sensitive diagnostic test for past or current exposure to an infectious agent, as the AIDS virus: a sample of blood is added to proteins from the agent, and any antibodies that combine with the proteins, indicating a history of infection, are detected by adding a test antibody linked to an enzyme that causes a color change.
2. Biol. , Med. any similar test using proteins as a probe for the identification of antibodies or antigens.
[ e ( nzyme- ) l ( inked ) i ( mmuno ) s ( orbent ) a ( ssay ) ]