Acquired – means that the disease is not hereditary but develops after birth from contact with a disease causing agent (in this case, HIV).

Immunodeficiency – means that the disease is characterized by a weakening of the immune system.

Syndrome – refers to a group of symptoms that collectively indicate or characterize a disease. In the case of AIDS this can include the development of certain infections and/or cancers, as well as a decrease in the number of certain cells in a person’s immune system.

A diagnosis of AIDS is made by a physician using specific clinical or laboratory standards.