injection

Noun

injection (countable and uncountable, plural injections)

1. The act of injecting, or something that is injected.
   • For some indications in PET imaging, it is necessary for radiopharmaceutical injections to be administered contralaterally or pedally to the disease process2010, Paul Shreve, David W. Townsend, Clinical PET-CT in Radiology: Integrated Imaging in Oncology, →ISBN, page 78
2. A specimen prepared by injection.
3. A morphism from either one of the two components of a coproduct to that coproduct.
4. The act of inserting materials like concrete grout or gravel by using high pressure pumps.
5. (figuratively) The supply of additional funding to a person or a business.
   • The troubled business received a much-needed cash injection.
6. A relation on sets (X,Y) that associates each element of Y with at most one element of X.

   Synonyms:

   injective function

7. (computer security) The insertion of program code into an application, URL, hardware, etc.; especially when malicious or when the target is not designed for such insertion.
   • a SQL injection exploit allowing a malicious user to modify a database query
8. The act of putting a spacecraft into a particular orbit, especially for changing a stable orbit into a transfer orbit, e.g. trans-lunar injection.
   • It had been determined that one of the whip turnstile antennas had broken off from Explorer 1 shortly after injection into orbit, so these were eliminated.2015, Henry L. Richter, America's Leap Into Space
9. A function that maps distinct x in the domain to distinct y in the codomain; formally, a f: X → Y such that f(a) = f(b) implies a = b for any a, b in the domain.
10. Something injected subcutaneously, intravenously, or intramuscularly by use of a syringe and a needle.
11. Congestion (of a body part, with blood or other fluid), such as hyperemia.
    • conjunctival injection
12. (internal combustion engines) Fuel injection: the pressurized introduction of fuel into a cylinder.
    • direct injection
    • tuned port injection
13. (steam engines) The act of throwing cold water into a condenser to produce a vacuum.
14. (steam engines) The cold water thrown into a condenser to produce a vacuum.