subframe

/S AH1 B F R EY0 M/
noun
  1. 1

    A subsidiary frame (chunk of data).

  2. 2

    A structural component of a vehicle, such as an automobile or aircraft, that uses a discrete, separate structure within a larger body-on-frame or unit body to carry certain components, such as the engine, drivetrain, or suspension.

  3. 3

    One of the HTML frames that make up a frameset.

Source: https://en.wiktionary.org/wiki/subframe