in·​jec·​tion | \ in-ˈjek-shən How to pronounce injection (audio) \

Definition of injection

1a : an act or instance of injecting
b : the placing of an artificial satellite or a spacecraft into an orbit or on a trajectory also : the time or place at which injection occurs
2 : something (such as a medication) that is injected
3 : a mathematical function that is a one-to-one mapping — compare bijection, surjection

Examples of injection in a Sentence

The medicine cannot be taken orally; it must be given by injection. an injection of a painkiller The struggling company needed an injection of cash.
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Recent Examples on the Web To carry out the euthanasia, the physician drugged the patient’s coffee without her knowledge and then had family members restrain the woman while delivering the fatal injection., "The court ruled that in rare cases of euthanasia that were being performed on patients with severe dementia — and who had earlier made a written request for euthanasia — the doctor ‘‘did not have to verify the current desire to die.’’," 12 Sep. 2019 Jordan was required to appear regularly at the outpatient department’s Northeast Washington offices, not only to get his injections but to have his urine tested at least once a month for traces of intoxicants. Washington Post, "No sane reason," 4 Sep. 2019 The women rushed to the emergency room hours after getting the injections. Samantha Lauriello,, "Botched Lip Injections Leave Multiple Arizona Women With Serious Infections After They Got Them Cheaply Done," 20 Aug. 2019 This is a much less violent way than the electric chair and the latest lethal injection [Dennis McGuire’s 2014 death] that took 26 minutes. Jeremy Pelzer,, "AG Dave Yost suspends but defends Ohio’s facial-recognition software: Capitol Letter," 15 Aug. 2019 Sandoval received a cortisone shot in his elbow and a MRI on Sunday, but the injection did little to mask the persistent pain and inflammation the switch-hitting infielder is forced to deal with. Kerry Crowley, The Mercury News, "Pablo Sandoval’s elbow injury a crushing blow to Giants team that needs his energy," 14 Aug. 2019 Eventually, Elway said a Broncos trainer referred him to a hand specialist, which led to a form of treatment that possibly included getting injections of prescription medication. Jarrett Bell, USA TODAY, "John Elway reveals Dupuytren's contracture diagnosis, promotes awareness for hand condition," 8 Aug. 2019 Patients with certain chronic eye diseases, like glaucoma and macular degeneration, typically either use inefficient eyedrops or have to get injections directly into their eyes. Kiona N. Smith, Ars Technica, "Delivering drugs directly to the eye using microneedles that dissolve," 9 Nov. 2018 The company, which has struggled for years, has been selling assets, closing stores and getting cash injections to stay afloat from Mr. Lampert, a financier who is its chief executive, chairman, largest shareholder and biggest creditor. Suzanne Kapner, WSJ, "Sears Reports Widening Losses and Tumbling Sales," 13 Sep. 2018

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'injection.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

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First Known Use of injection

15th century, in the meaning defined at sense 1a

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Statistics for injection

Last Updated

24 Oct 2019

Time Traveler for injection

The first known use of injection was in the 15th century

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More Definitions for injection


How to pronounce injection (audio)

English Language Learners Definition of injection

: the act or process of forcing a liquid medicine or drug into someone or something by using a special needle
: the act or process of forcing a liquid into something
: the addition of something (such as money) that is needed to support something


in·​jec·​tion | \ in-ˈjek-shən How to pronounce injection (audio) \

Kids Definition of injection

: an act or instance of forcing a fluid (as a medicine) into a part of the body by using a special needle Insulin can be given by injection.


in·​jec·​tion | \ in-ˈjek-shən How to pronounce injection (audio) \

Medical Definition of injection

1a : the act or an instance of injecting a drug or other substance into the body
b : a solution (as of a drug) intended for injection (as by catheter or hypodermic syringe) either under or through the skin or into the tissues, a vein, or a body cavity
c : an act or process of injecting vessels or tissues also : a specimen prepared by injection
2 : the state of being injected : congestion — see circumcorneal injection

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More from Merriam-Webster on injection

Rhyming Dictionary: Words that rhyme with injection

Spanish Central: Translation of injection

Nglish: Translation of injection for Spanish Speakers

Britannica English: Translation of injection for Arabic Speakers Encyclopedia article about injection

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