immunize

[ im-yuh-nahyz, ih-myoo-nahyz ]

verb (used with object)

, im·mu·nized, im·mu·niz·ing.

1. to make immune, or protected from a disease or the like:

   They are organizing a massive health campaign to immunize millions of children.

   George Washington's army immunized its soldiers against smallpox.

2. to shield, exempt, or protect:

   There is no moral or legal basis for immunizing victorious nations from scrutiny over their actions in a war.

3. Law. to grant (a witness) exemption from criminal prosecution, legal liability, or punishment on certain conditions:

   In exchange for her testimony, the court agreed to immunize the witness against prosecution for criminal activities committed during the relevant period.

immunize

/ ˈɪmjʊˌnaɪz /

verb

1. to make immune, esp by inoculation

Derived Forms

• ˈimmuˌnizer, noun
• ˌimmuniˈzation, noun

Other Words From

• im·mu·niz·er noun
• hy·per·im·mu·nize verb (used with object) hyperimmunized hyperimmunizing
• o·ver·im·mu·nize verb (used with object) overimmunized overimmunizing

Word History and Origins

Origin of immunize¹

First recorded in 1890–95; immune + -ize

Example Sentences

California requires elementary and secondary school students to be immunized against a range of diseases unless they have a medical exemption; the COVID-19 shot is recommended but not mandatory.

From Los Angeles Times

Trump does this as a way of immunizing himself against charges that he is racist.

From Salon

Last year, uninsured adults were able to get free vaccines through the federal Bridge Access Program, where people could get immunized at federally qualified health centers, as well as CVS and Walgreens.

From Los Angeles Times

“Fewer people got immunized this year compared to last year at this time,” Chin-Hong said.

From Los Angeles Times

Individuals who are not immunized and haven’t had measles are at risk of developing symptoms one to three weeks after they were exposed.

From Los Angeles Times

Related Words

• inoculate
• protect
• vaccinate

Immunize Vs. Vaccinate Vs. Inoculate

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

In the context of medicine, immunize, inoculate, and vaccinate 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 provide what amounts to long-term immunity, while others only lead to 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.

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

Quiz yourself on immunize vs. vaccinate vs. inoculate!

True or False?

Immunize, vaccinate, and inoculate can be correctly used in some overlapping ways.