Monoclonal antibody: Laboratory-produced substances that can locate and bind to cancer cells wherever they are in the body. Many monoclonal antibodies are used in cancer detection or therapy; each one recognizes a different protein on certain cancer cells. Monoclonal antibodies can be used alone, or they can be used to deliver drugs, toxins, or radioactive material directly to a tumor.

Aneurysm: Localised ballooning of the aorta or an artery, potentially causing pressure on adjacent structures and liability to rupture.