injection

American  

[in-jek-shuhn] / ɪnˈdʒɛk ʃən /

noun

• injections
  plural

1. the act of injecting.

2. something that is injected.

3. a liquid injected into the body, especially for medicinal purposes, as a hypodermic or an enema.

4. state of being hyperemic or bloodshot.

5. Mathematics. a one-to-one function.

6. Also called insertion. Aerospace. the process of putting a spacecraft into orbit or some other desired trajectory.

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injection British  

/ ɪnˈdʒɛkʃən /

noun

1. fluid injected into the body, esp for medicinal purposes

2. something injected

3. the act of injecting

4. 1. the act or process of introducing fluid under pressure, such as fuel into the combustion chamber of an engine

   2. ( as modifier )

      injection moulding

5. maths a function or mapping for which f( x ) = f( y ) only if x = y See also surjection bijection

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injection Scientific  

/ ĭn-jĕk′shən /

1. A substance that is introduced into a organism, especially by means of a hypodermic syringe, as a liquid into the veins or muscles of the body.

2. A function that maps each member of one set (the domain) to exactly one member of another set (the range).

3. Compare bijection surjection

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Other Word Forms

Derived Forms

• reinjection
  noun
• superinjection
  noun
• injective
  adjective
• postinjection
  adjective

Inflected Forms

Nouns

• injections
  plural

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Etymology

Origin of injection

First recorded in 1535–45, injection is from the Latin word injectiōn- (stem of injectiō ). See inject, -ion

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Explanation

An injection is a shot, or a dose of medicine given by way of a syringe and a needle. When you get jabbed in the arm with a tetanus vaccine, that's an injection. The medical kind of injection forces a small amount of a drug under the skin or directly into a muscle. Other injections are similar in that they involve a liquid being forced by pressure, like the fuel injection in a car, which pushes gasoline directly into the engine. Since the 1600s, injection has been used to mean "forcing a fluid into a body," from the Latin inicere, "to throw in" or "to throw on."

Example Sentences

See Examples For:

injection injections

So, Ohtani kept trying to work his way back to the mound for weeks after receiving a lubricating Orthovisc injection in his knee at the beginning of the All-Star break.

From Los Angeles Times ● Oct. 14, 2026

Her case is now in uncharted territory as she is thought to be the only person to have survived an execution attempt by lethal injection.

From BBC ● Oct. 13, 2026

One can only hope that this disturbing episode will cause reconsideration of our half-century-long experiment with lethal injection, but I’m not so sure.

From The Wall Street Journal ● Oct. 12, 2026

An experimental injection that causes fat cells to destroy themselves has shown promising results in early human trials, significantly reducing dangerous fat hidden deep inside the abdomen.

From Science Daily ● Oct. 11, 2026

After a nurse appeared at St. Tarkmanchatz without warning and plunged a clumsy cholera injection into the arm of each student, Liyana stayed home from school for days with a raging fever.

From "Habibi" by Naomi Shihab Nye

The data doesn’t specify where on their bodies men got injections.

From The Wall Street Journal ● Oct. 16, 2026

Cats, Ms. Fullerton explains, are ideal companions for men and women of letters, whose “lonely occupation” may be alleviated by furry injections of playfulness and curiosity.

From The Wall Street Journal ● Oct. 16, 2026

Studies have found that people who come off weight loss injections can regain their lost pounds four times faster than those who stop conventional diet and exercise.

From BBC ● Oct. 14, 2026

All had continued to experience symptoms despite at least three months of conventional care, including physical therapy, anti-inflammatory medications, and injections into the knee.

From Science Daily ● Oct. 14, 2026

Every day Pitezel joined three dozen other men in the daily ritual of “passing through the line” to receive his injections.

From "The Devil in the White City" by Erik Larson

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Related Words

• dose
• needle

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