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

Novo this week laid out an ambitious strategy to reignite growth beyond its top-selling Wegovy and Ozempic injections, which face patent expirations in key markets in the early 2030s. — Annika Kim Constantino,elsa Ohlen, CNBC, 25 Sep. 2026

Daily insulin injections can be physically and emotionally challenging for people with type 2 diabetes. — Emily Kay Votruba, EverydayHealth.com, 25 Sep. 2026

Ramey became the sixth inmate executed in Texas this year, with the state set to carry out three more lethal injections over the next two months. — James Cirrone, FOXNews.com, 24 Sep. 2026

The 34-year-old Judge received a Platelet-Poor Plasma (PPP) injection in his calf on Monday. — Peter Sblendorio, New York Daily News, 24 Sep. 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