herd immunity
noun
the immunity or resistance to a particular infection that occurs in a group of people or animals when a very high percentage of individuals have been vaccinated or previously exposed to the infection.
Words nearby herd immunity
hercules'-club,
hercules-club,
hercynian,
hercynite,
herd,
herd immunity,
herd instinct,
herd tester,
herd's-grass,
herd-book,
herder
Medical definitions for herd immunity
herd immunity
[ hûrd ]
n.
Resistance to the spread of infectious disease in a group because susceptible members are few, making transmission from an infected member unlikely.
The immunologic status of a population, determined by the ratio of resistant to susceptible members and their distribution.