noun in·jec·tion \in-ˈjek-shən\

: 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

Full Definition of INJECTION

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
:  something (as a medication) that is injected
:  a mathematical function that is a one-to-one mapping — compare bijection, surjection

Examples of INJECTION

  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.

First Known Use of INJECTION

15th century
INJECTION Defined for Kids


noun in·jec·tion \in-ˈjek-shən\

Definition of INJECTION for Kids

:  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


noun in·jec·tion \in-ˈjek-shən\

Medical Definition of INJECTION

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
:  the state of being injected :  congestion—see circumcorneal injection
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