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

Every year, more than 3 billion injections are administered outside traditional healthcare settings in the United States. — Irina Butler, Boston Herald, 10 July 2026

Those interventions will include draining his left knee, as manager Dave Roberts confirmed before the game Friday, and likely an injection, according to a person with knowledge of the situation who was not authorized to speak publicly. — Maddie Lee, Los Angeles Times, 10 July 2026

In February 2024, the prison system attempted to put Creech to death by lethal injection, but failed to do so when members of the execution team couldn’t find a suitable vein in his body for an IV to deliver the drugs. — Kevin Fixler, Idaho Statesman, 10 July 2026

Prompt injection, credential leakage and model supply chain risk are all being exploited right now. — Priya Sawant, Forbes.com, 10 July 2026

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