(epidemiology) The indirect protection against the spread of a contagious disease in a given population caused by the immunity of a significant proportion of the population to that particular disease; the immunity may have been obtained through having survived the infection or through vaccination.

(law) A legal doctrine by which the sovereign or state cannot commit a legal wrong and is immune from civil suit or criminal prosecution.

(law) A legal doctrine by which the royal sovereign or royally governed state cannot commit a legal wrong and is immune from civil suit or criminal prosecution.

(immunology) The translocation of active humoral immunity from one individual to another in the form of custom-made antibodies.

(biology) Any antiparasite defence mounted for the benefit of individuals other than the actor.

(law, US) A doctrine protecting some government officials from suit if no prior court decision had declared similar conduct to be actionable, or if they acted in good faith.

(law) A doctrine providing immunity from suit by private parties for certain government officials and witnesses in judicial proceedings, even if the act or testimony was illegal, false, or made in bad faith.

immunity and immune response granted by the innate immune system

immunity and immune response granted by the adaptive immune system

(epidemiology) Synonym of herd immunity