noun
immunity
Protection from a disease, obligation, or legal consequence.
Where it comes from
Immunity ordinarily means protection from a disease, obligation, or legal consequence. Immunity came through French from Latin immunitas, exemption from a public service or charge. Immunis meant exempt or free from obligation, built from in-, not, and a relative of munia, duties or services. English first used immunity for freedom from duties and liabilities. Nineteenth-century medicine reused that legal and civic idea: a person protected against a disease was treated as exempt from it.
How the meaning developed
The immune system was named afterward.
Sources
Definitions adapted from Open English WordNet where applicable. License and attribution. Word-history text comes from Lexifour’s sourced social research; pages are assembled automatically, not individually fact-checked on every update.
Updated 2026-10-05. Report a correction.