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

Gabby Jones | Bloomberg | Getty Images Novo Nordisk is suing Hims & Hers over the telehealth provider's copycat versions of Novo's Wegovy obesity pill and injections. —Josephine Rozzelle, CNBC, 9 Feb. 2026

Patriots quarterback Drake Maye, who received a pain-relieving injection in his throwing shoulder before the game, was sacked six times and had three turnovers in the 29-13 loss. —Ryan Gaydos, FOXNews.com, 9 Feb. 2026

Doctors, meanwhile, are bracing for a flood of new patients seeking the injections – some, like Chamadia, who medically qualify, and others drawn by the lure of a quick fix. —Ayushi Shah, CNN Money, 8 Feb. 2026

Under this plan, a $900 IVF injection is reduced by up to 85%. —Torie Bosch, STAT, 7 Feb. 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