inject

inject — verb

1. To deliver a liquid medicine or drug beneath the skin using a hollow needle, typ

1.verbtransitiveB1
Definition

To deliver a liquid medicine or drug beneath the skin using a hollow needle, typically into a muscle or a vein.

Example

Diya's doctor injects insulin into her abdomen every morning before breakfast.

inject + substance + into + body part

The nurse injected the flu vaccine into Benjamin's upper arm.

Common collocations
  • inject insulin
  • inject a vaccine
  • inject a dose of [drug]
  • inject into the muscle
  • inject into a vein
  • inject with a needle
Synonyms
  • administer

    broader term; can mean giving medicine by mouth, injection, or other methods

  • shoot up

    very informal; almost always refers to injecting illegal drugs

Grammar Patterns

inject + object (substance) + into + person/body part

Usage Note

Object is typically the substance being injected (insulin, vaccine, anesthetic), not the needle. The recipient can be introduced with into (inject insulin into her abdomen) or as a passive subject (she was injected with insulin).

Common Mistakes

❗ 'The nurse injected a needle into my arm.' ✅ 'The nurse injected the vaccine into my arm.' — You inject the substance, not the needle or syringe.

2. To add a new quality, feeling, idea, or amount of money to a situation, discussi

2.verbtransitiveB2
Definition

To add a new quality, feeling, idea, or amount of money to a situation, discussion, or system, often with the aim of improving or changing it.

Example

Caio's jokes injected some much-needed humor into the tense business meeting.

inject humor into [situation]

The central bank decided to inject two billion dollars into the struggling banking system.

inject money into [system]

Common collocations
  • inject humor into
  • inject energy into
  • inject new life into
  • inject cash into
  • inject capital into
  • inject competition into
Synonyms
  • introduce

    more neutral, less forceful; does not suggest sudden addition

  • infuse

    suggests gradual or thorough spreading through something

  • add

    more general; does not imply force or novelty

Antonyms
  • remove

    to take something out of a situation

Grammar Patterns

inject + abstract noun (humor, energy, money) + into + situation/system

Usage Note

Common with abstract objects such as humor, energy, enthusiasm, money, cash, life, competition. The preposition into always follows the object. Frequently used in business and financial contexts for injecting capital.

Common Mistakes

❗ 'She injected humor in the conversation.' ✅ 'She injected humor into the conversation.' — The figurative sense always takes into, not in.

Word family

  • injection
    nounB1
  • injectable
    adjectiveC1
  • injector
    nounC1

Synonym discussion

Sense: verb/1

These verbs all relate to putting a substance into the body, but they differ in method and register. Inject is the most neutral and specific term for using a needle and syringe to deliver medicine. Administer is much broader — it covers giving medicine by mouth, through a skin patch, by inhalation, or by injection. Vaccinate and inoculate both refer specifically to giving a vaccine to protect against disease; inoculate can also mean exposing someone to a mild form of a disease to build immunity. Shoot up is highly informal and almost always implies injecting illegal drugs. For example: a doctor administers an oral antibiotic (pill form, not injected), a clinic vaccinates children against measles (by injection, but the focus is on the protection, not the method), and a person might shoot up heroin (illicit, slang).

inject ↗administer ↗vaccinateinoculateshoot up ↗

Common collocations

Nouns

Adverbs

Phrases

  • inject into
  • inject with
  • inject a dose of
  • inject new life into

Prepositions

Etymology

LatinFrenchEnglish

Inject comes from the Latin word injectus, meaning 'thrown in.' It was formed from in- ('in') and iacere ('to throw'). The word entered English through French in the 1500s, first with a literal sense of 'throwing or casting in,' and later became associated with medical procedures using syringes.