Welcome to the Glossary of Commonly Used HIV/AIDS Terms! This feature provides a number of uses. Learn basic definitions, brush up on medical terms or provider lingo, or use the glossary as a reference guide in understanding the many acronyms found in the HIV/AIDS language. Whatever your needs, use the glossary to meet them.

Just click a letter below to see the terms listed.

A

B

C

D

E

F

H

I

K

L

M

N

O

P

Q

R

S

T

U

V

W

Opportunistic Infection (OI) or Opportunistic Condition

An infection or cancer that occurs in persons with weak immune systems due to HIV, cancer or immunosuppressive drugs such as corticosteroids or chemotherapy. Kaposi's Sarcoma (KS), pneumocystis pneumonia (PCP), toxoplasmosis and cytomegalovirus (CMV) are all examples of opportunistic infections.