[ vak-suh-neyt ]
/ ˈvæk səˌneɪt /
Save This Word!
See synonyms for: vaccinate / vaccinated on Thesaurus.com

verb (used with object), vac·ci·nat·ed, vac·ci·nat·ing.

to inoculate with the vaccine of cowpox so as to render the subject immune to smallpox.
to inoculate with the modified virus of any of various other diseases, as a preventive measure.

verb (used without object), vac·ci·nat·ed, vac·ci·nat·ing.

to perform or practice vaccination.



Loosen up your grammar muscles because it’s time to test your knowledge on verb tenses!
Question 1 of 6
The verb tenses can be split into which 3 primary categories?

Meet Grammar Coach

Write or paste your essay, email, or story into Grammar Coach and get grammar helpImprove Your Writing

Meet Grammar Coach

Improve Your Writing
Write or paste your essay, email, or story into Grammar Coach and get grammar help

Origin of vaccinate

First recorded in 1800–10; back formation from vaccination


pre·vac·ci·nate, verb (used with object), pre·vac·ci·nat·ed, pre·vac·ci·nat·ing.re·vac·ci·nate, verb (used with object), re·vac·ci·nat·ed, re·vac·ci·nat·ing.un·vac·ci·nat·ed, adjective
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2021


What’s the difference between vaccinate, inoculate, and immunize?

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

Vaccinate 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 inoculate has other meanings outside the context of medicine, in modern healthcare it’s typically used interchangeably with vaccinate (though it’s used less commonly).

Immunize is slightly different—it means to provide immunity from a specific disease. While the goal of vaccinating someone is often to immunize them, not all vaccines provide permanent immunity. Some vaccines cause the body to become immune to a disease for a very long time, while others only lead to a temporary immunity, 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 immunity gained from the earlier vaccination.

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

Quiz yourself on vaccinate vs. inoculate vs. immunize!

True or False?

Vaccinate, inoculate, and immunize can be correctly used in some overlapping ways.

How to use vaccinate in a sentence

British Dictionary definitions for vaccinate

/ (ˈvæksɪˌneɪt) /


to inoculate (a person) with a vaccine so as to produce immunity against a specific disease

Derived forms of vaccinate

vaccinator, noun
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

Medical definitions for vaccinate

[ văksə-nāt′ ]


To inoculate with a vaccine in order to produce immunity to an infectious disease such as diphtheria or typhus.

Other words from vaccinate

vacci•na′tor n.
The American Heritage® Stedman's Medical Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Company. Published by Houghton Mifflin Company.