injection

noun

in·​jec·​tion in-ˈjek-shən 

1

a

: 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.

Recent Examples on the Web

Most commonly, this happens from hormonal birth control, such as birth control pills, implants, or injections. —Wendy Wisner, Health, 24 Oct. 2025

Additionally, just hours after ChatGPT Atlas launched, Brave, an open-source browser company, posted a blog detailing several attacks AI browsers are particularly vulnerable to, including indirect prompt injections. —Beatrice Nolan, Fortune, 23 Oct. 2025

The state will use an injection of pentobarbital to execute Ricks in the death chamber at the Texas Department of Criminal Justice Huntsville Unit. —Emerson Clarridge, Fort Worth Star-Telegram, 22 Oct. 2025

Past outages on this scale have been caused by a wide variety of errors, including faulty updates, the accidental injection of bad code, or a change to third-party software that doesn’t play nicely with a service. —Alexandra Banner, CNN Money, 21 Oct. 2025

Word History

First Known Use

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

Phrases Containing injection

• fuel injection
• hypodermic injection
• injection molding

Rhymes for injection

• abjection
• advection
• affection
• bijection
• bisection
• collection
• complexion
• confection
• connection
• connexion
• convection
• correction

Kids Definition

injection

noun

in·​jec·​tion in-ˈjek-shən 

1

: an act or instance of injecting

2

: something (as a medical drug) that is injected

Medical Definition

injection

noun

in·​jec·​tion in-ˈjek-shən 

1

a

: 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