inject

verb

in·​ject in-ˈjekt 

injected; injecting; injects

transitive verb

1

a

: to introduce into something forcefully

inject fuel into an engine

b

: to force a fluid into (as for medical purposes)

inject a drug into the bloodstream

2

: to introduce as an element or factor in or into some situation or subject

… condemning any attempt to inject religious bigotry into the campaign.

—Current Biography

injectable

in-ˈjek-tə-bəl 

adjective or noun

injector

in-ˈjek-tər 

noun

Synonyms of inject

• insert
• introduce

Examples of inject in a Sentence

She told a few jokes to inject a little humor into her speech.

We need to inject some life into this party.

Recent Examples on the Web

The tests found that during the checkout process, Phia opened a background tab and injected its own cookie into the sales process, overriding legitimate referrals from other publishers. — Bloomberg, Fortune, 12 Aug. 2026

Hydrogen is injected into the cylinders at much lower pressure and temperature than in a diesel engine, and a spark causes ignition. — Jonathan M. Gitlin, ArsTechnica, 12 Aug. 2026

The patient injects them for up to two weeks to encourage the ovaries to produce as many healthy eggs as possible. — Jen Christensen, CNN Money, 11 Aug. 2026

But Marais cautions that Starship's size and the much more frequent launches that will be needed to deploy the vast constellations would result in an overall increase in the pollution injected into the upper atmosphere. — Tereza Pultarova, Space.com, 11 Aug. 2026

Word History

Etymology

Latin injectus, past participle of inicere, from in- + jacere to throw — more at jet

First Known Use

1601, in the meaning defined at sense 1a

Rhymes for inject

• affect
• aspect
• bedecked
• bisect
• collect
• connect
• correct
• deflect
• detect
• direct
• dissect
• effect

Kids Definition

inject

verb

in·​ject in-ˈjekt 

1

a

: to throw, drive, or force into something

inject fuel into an engine

b

: to force a fluid into (a part of the body) especially for medical reasons

2

: to introduce as an additional element

injected humor into her speech

injectable

-ˈjek-tə-bəl 

adjective

injector

-ˈjek-tər 

noun

Medical Definition

inject

transitive verb

in·​ject in-ˈjekt 

1

: to force a fluid into (a vessel, cavity, or tissue) for preserving, hardening, or coloring structures

2

: to introduce (as by injection or gravity flow) a fluid into (a living body) especially for the purpose of restoring fluid balance, treating nutritional deficiencies or disease, or relieving pain

also : to treat (an individual) with injections