noun, plural im·mu·ni·ties.
- the exemption of ecclesiastical persons and things from secular or civil liabilities, duties, and burdens.
- a particular exemption of this kind.
- immune serum globulin,
- immune surveillance,
- immune system,
- immune thrombocytopenic purpura,
- immunity bath,
Origin of immunity
noun plural -ties
late 14c., "exempt from service or obligation," from Old French immunité and directly from Latin immunitatem (nominative immunitas) "exemption from performing public service or charge," from immunis "exempt, free," from assimilated form of in- "not, opposite of" (see in- (1)) + munis "performing services" (cf. municipal), from PIE *moi-n-es-, suffixed form of root *mei- "to change" (see mutable). Medical sense "protection from disease" is 1879, from French or German.
The ability of the body to resist or fight off infection and disease.