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injection

noun in·jec·tion \ in-ˈjek-shən \
|Updated on: 15 Aug 2018

Definition of injection

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

See injection defined for English-language learners

See injection defined for kids

Examples of injection in a Sentence

  1. The medicine cannot be taken orally; it must be given by injection.

  2. an injection of a painkiller

  3. The struggling company needed an injection of cash.

Recent Examples of injection from the Web

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'injection.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

First Known Use of injection

15th century

in the meaning defined at sense 1a

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INJECTION Defined for English Language Learners

injection

noun

Definition of injection for English Language Learners

  • : the act or process of forcing a liquid medicine or drug into someone or something by using a special needle

  • : the act or process of forcing a liquid into something

  • : the addition of something (such as money) that is needed to support something

INJECTION Defined for Kids

injection

noun in·jec·tion \ in-ˈjek-shən \

Definition of injection for Students

: an act or instance of forcing a fluid (as a medicine) into a part of the body by using a special needle
  • Insulin can be given by injection.

Medical Dictionary

injection

noun in·jec·tion \ in-ˈjek-shən \

medical Definition of injection

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

Learn More about injection

  1. See words that rhyme with injection Spanish Central: Translation of injection Nglish: Translation of injection for Spanish speakers Britannica English: Translation of injection for Arabic speakers Britannica.com: Encyclopedia article about injection

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