inoculate

American  

[ih-nok-yuh-leyt] / ɪˈnɒk yəˌleɪt /

verb (used with object)

inoculated, inoculating

1. to implant (a disease agent or antigen) in a person, animal, or plant to produce a disease for study or to stimulate disease resistance.

2. to affect or treat (a person, animal, or plant) in this manner.

3. to introduce (microorganisms) into surroundings suited to their growth, as a culture medium.

4. to imbue (a person), as with ideas.

   Synonyms:

   infuse, indoctrinate

5. Metallurgy. to treat (molten metal) chemically to strengthen the microstructure.

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verb (used without object)

inoculated, inoculating

1. to perform inoculation.

inoculate British  

/ ɪˈnɒkjʊˌleɪt /

verb

1. to introduce (the causative agent of a disease) into the body of (a person or animal), in order to induce immunity

2. (tr) to introduce (microorganisms, esp bacteria) into (a culture medium)

3. (tr) to cause to be influenced or imbued, as with ideas or opinions

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Usage

What’s the difference between inoculate, vaccinate, and immunize? In the context of medicine, inoculate, vaccinate, 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 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. Want to learn more? Read the full breakdown of the difference between inoculate, vaccinate, and immunize.

Other Word Forms

• inoculation noun
• inoculative adjective
• inoculator noun
• noninoculative adjective
• reinoculate verb
• self-inoculated adjective
• uninoculated adjective
• uninoculative adjective

Etymology

Origin of inoculate

First recorded in 1400–50; late Middle English, from Latin inoculātus, past participle of inoculāre “to graft by budding, implant,” equivalent to in- “in” + -oculā- (stem of -oculāre “to graft,” derivative of oculus “eye, bud”) + -tus past participle suffix; see in- ²

Explanation

If you inoculate someone, you try to make him immune to a disease by injecting a little dose of it, so his body can make antibodies to fight it off. When you were little you probably got a vaccine to inoculate you against smallpox. When inoculate first came into English in the 15th century, it referred to inserting a bud onto another plant. Now you’re more likely to hear it used to describe the process of building up immunity to a disease by giving someone a vaccine, which also involves the insertion of foreign matter. You can also inoculate someone metaphorically, with ideas.

Example Sentences

The government was determined not to budge, perhaps hopeful much of it was noise and their mountainous majority would inoculate them from a minority of grumblers.

From BBC • Jun. 27, 2025

They hope that antibodies in the milk can inoculate them against the virus.

From Slate • Dec. 4, 2024

Farmers can combat the mealybugs by giving vaccines to the trees to inoculate them from the virus.

From Science Daily • Apr. 23, 2024

Both of them reflect Jude’s disdain for the ways people inoculate themselves from harsh truths in order to enjoy a false, sunnier version of life.

From Los Angeles Times • Mar. 20, 2024

Should it then attack a healthy person there is danger that it will inoculate him with the disease.

From "An American Plague: The True and Terrifying Story of the Yellow Fever Epidemic of 1793" by Jim Murphy

Related Words

• inject
• vaccinate