Mechanism

noun

1. (within a machine or machinery) Any mechanical means for the conversion or control of motion, or the transmission or control of power.
2. Any combination of cams, gears, links, belts, chains and logical mechanical elements.
3. A group of entities, such as objects, that interact together.

   "political machine"

4. A mental, physical or chemical process.
5. Any process of, or system designed to manage useful energy conversion.