| HIV | the virus that causes acquired immune deficiency syndrome (AIDS) |
| AIDS | a syndrome caused by the human immunodeficiency virus (HIV) that renders immune cells ineffective, permitting opportunistic infections, malignancies, and neurologic diseases to develop; transmitted sexually or through contaminated blood |
| EIA | a test that screens for the presence of HIV antibodies in the blood |
| ELISA | Enzyme Linked Immunoassay |
| Immune System | a system (including the thymus and bone marrow and lymphoid tissues) that protects the body from foreign substances and pathogenic organisms by producing the immune response |