Immunocompromised
Etymology
Built from “immuno-,” from Latin “immunis” (exempt from burden), and “compromised,” from Latin “compromittere” (to make a mutual promise), which drifted through the sense of “to expose to risk” into “to impair.” So the word describes a defense system whose protective exemption has been undermined. It became common as transplants, chemotherapy, and HIV made the condition widespread.
adjective · /ih-MYOO-noh-kom-pruh-myzd/
Having an immune system that is weakened and less able to fight off infections.
What it names
The vulnerable state — from illness, age, or medication — in which ordinary germs become genuine dangers, explaining why a mild bug for one person can hospitalize another.
Example
Because chemotherapy left her immunocompromised, her family wore masks around her all winter.
Related idea
Being immunocompromised is a weakened immune system; an autoimmune condition is an overactive one attacking the body itself. Both are malfunctions of the same defenses, but one fails to fight real threats while the other fights imaginary ones.