[ vak-suh-ney-shuhn ]
/ ˌvæk səˈneɪ ʃən /
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noun Medicine/Medical.
the act or practice of vaccinating; inoculation with vaccine.


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Origin of vaccination

1800–10; vaccine (adj.) + -ation

OTHER WORDS FROM vaccination

Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2022


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

In the context of medicine, the words vaccination, inoculation, 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 vaccinate, inoculate, and immunize.

Quiz yourself on vaccination vs. inoculation vs. immunization!

True or False?

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

How to use vaccination in a sentence

British Dictionary definitions for vaccination

/ (ˌvæksɪˈneɪʃən) /

the act of vaccinating
the scar left following inoculation with a vaccine
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Scientific definitions for vaccination

[ văk′sə-nāshən ]

Inoculation with a vaccine in order to protect against a particular disease.
A scar left on the skin by vaccinating.
The American Heritage® Science Dictionary Copyright © 2011. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.

Cultural definitions for vaccination

[ (vak-suh-nay-shuhn) ]

Inoculation with a vaccine to produce immunity to a particular infectious disease.

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.