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

Enhanced oil recovery uses techniques such as carbon dioxide injection to increase the amount of crude oil produced from an oil field. — Jenny Lee, CNBC, 5 Oct. 2026

Over in the Nostrand Houses in Sheepshead Bay, City Hall and NYCHA have announced a cash injection of $607 million for repairs and improvements, courtesy of the Housing Preservation Trust. — New York Daily News Editorial Board, New York Daily News, 4 Oct. 2026

Stanton also reviewed Tennessee’s procedures after Lee called off a different execution in 2022 and found the state did not comply with its own lethal injection process. — Jeffrey Collins, Los Angeles Times, 4 Oct. 2026

The prognosis for a Tennessee woman who survived two doses of lethal injection is still unclear, according to her lawyer, who said doctors are still trying to clear the lethal drug administered during her execution attempt. — Claire Carter, The Washington Examiner, 4 Oct. 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