Chassis

A chassis (, ; plural "chassis" from French châssis ) (plural chassis) consists of a framework that supports an inanimate (non-living) object. This is much like an animal's skeleton, for example in a car.
Examples of use.
In a car, the term chassis means the frame (the metal "skeleton") plus the engine, transmission (gear shift), driveshaft, differential (gears which keep the back wheels moving correctly), and suspension (springs which keep the car above the ground). A body, which is usually not necessary to keep the car together, is built on top of the chassis to complete the car.