|n.||1.||The act of injecting or throwing in; - applied particularly to the forcible insertion of a liquid or gas, by means of a syringe, pump, etc.|
|2.||That which is injected; especially, a liquid inserted thrown into a cavity of the body by a syringe or pipe; a clyster; an enema.|
|3.||(Anat.) The act or process of filling vessels, cavities, or tissues with a fluid or other substance.|
|4.||(Steam Eng.) The act of throwing cold water into a condenser to produce a vacuum.|
|Noun||1.||injection - the forceful insertion of a substance under pressure|
|2.||injection - any solution that is injected (as into the skin)|
|3.||injection - the act of putting a liquid into the body by means of a syringe; "the nurse gave him a flu shot"|
inserting liquid medication or nutrients into the body with a syringe. A person with diabetes may use short needles or pinch the skin and inject at an angle to avoid an intramuscular injection of insulin.
|1.||(mathematics)||injection - A function, f : A -> B, is injective or
one-one, or is an injection, if and only if|
for all a,b in A, f(a) = f(b) => a = b.
I.e. no two different inputs give the same output (contrast many-to-one). This is sometimes called an embedding. Only injective functions have left inverses f' where f'(f(x)) = x, since if f were not an injection, there would be elements of B for which the value of f' was not unique. If an injective function is also a surjection then is it a bijection.
|2.||(reduction)||injection - An injection function is one which takes
objects of type T and returns objects of type C(T) where C is
some type constructor. An example is|
f x = (x, 0).
The opposite of an injection function is a projection function which extracts a component of a constructed object, e.g.
fst (x,y) = x.
We say that f injects its argument into the data type and fst projects it out.