immune

Where does the word "immune" come from? It comes from Latin immunis, and was adopted directly into English (1400s).

Immune’s story begins in Latin: immunis meant “exempt from duty.” Exempt from public service or duty, from in- (not) and munis (duty, service). It reached English by 1400s as immune. Narrowed to mean exempt or protected from disease or harm. Today, immune means protected against a disease or harmful influence, especially through the immune system.

1. Stage 1 · Latin · ancient immunis "exempt from duty", exempt from public service or duty, from in- (not) and munis (duty, service).
2. Stage 2 · English · 1400s immune "protected from disease, harm, or an obligation", narrowed to mean exempt or protected from disease or harm.