B2 [ C or U ] something such as energy, money, or information that is put into a system, organization, or machine so that it can operate:
I didn't have much input into the project (= the help I gave was small).
The power input will come largely from hydroelectricity.
[ C ] specialized electronics the part that carries information to a machine, or the place where this is connected:
The inputs for the CD-ROM are at the back of the computer.
an input device