[ ih-nok-yuh-ley-shuhn ]
/ ɪˌnɒk yəˈleɪ ʃən /
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the act or process of inoculating.
an instance of inoculating.


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Origin of inoculation

1400–50; late Middle English <Latin inoculātiōn- (stem of inoculātiō) an engrafting. See inoculate, -ion

OTHER WORDS FROM inoculation

non·in·oc·u·la·tion, nounpost·in·oc·u·la·tion, adjectivere·in·oc·u·la·tion, nounself-in·oc·u·la·tion, noun
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2023


What’s the difference between inoculation, vaccination, and immunization?

In the context of medicine, the words inoculation, vaccination, and immunization are often used in overlapping ways, and for good reason—they all involve the process of introducing a substance (especially a vaccine) into a person’s body with the goal of preventing them from getting a particular disease.

Vaccination is the most specific of the three terms, because it always involves introducing a vaccine, which usually consists of a small amount of a killed, weakened, or otherwise modified version of a disease (such as a virus or bacterium). While inoculation has other meanings outside the context of medicine, in modern healthcare it’s typically used interchangeably with vaccination (though it’s used less commonly).

Immunization is slightly different—it refers to the process of providing immunity from a specific disease. While the goal of vaccinating someone is often to immunize them, not all vaccines provide permanent immunity. Some vaccines provide what amounts to long-term immunity, while others only lead to a temporary protection, after which the body “forgets” how to make certain antibodies. In these cases, a booster shot or dose is often required, consisting of a follow-up vaccination to boost or renew the protection gained from the earlier vaccination.

Both vaccination and inoculation can refer to a shot or dose, as opposed to the process of providing or receiving such doses, as in I’m scheduled to get a vaccination on Friday. The word immunization can be used in the same way to refer to such a vaccination when it’s one that provides immunity, as in Have you received all of your immunizations?

Want to learn more? Read the full breakdown of the difference between inoculate, vaccinate, and immunize.

Quiz yourself on inoculation vs. vaccination vs. immunization!

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The words inoculation, vaccination, and immunization can be correctly used in some overlapping ways.

How to use inoculation in a sentence

Scientific definitions for inoculation

[ ĭ-nŏk′yə-lāshən ]

The introduction of a serum, a vaccine, or an antigenic substance into the body of a person or an animal, especially as a means to produce or boost immunity to a specific disease.
The introduction of a microorganism or an agent of disease into an host organism or a growth medium.

Other words from inoculation

inoculate verb
The American Heritage® Science Dictionary Copyright © 2011. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.

Cultural definitions for inoculation

[ (i-nok-yuh-lay-shuhn) ]

The introduction of an antigen into the body, usually by injection, in order to stimulate the production of antibodies to produce immunity to an infectious disease. (See immunization.)

The New Dictionary of Cultural Literacy, Third Edition Copyright © 2005 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.