By extension, a cartridge is a component in a case, ready for insertion and use into some bigger system. A cartridge may be consumable, but not necessarily.

This sounds desperately generic, I know. now for two examples:

  1. software came in cartridges for the VIC 20 and the Commodore 64. It still does for some game consoles. These cartridges contain basically a chunk of ROM, which means that they are instantly available to the system.
  2. Some film formats also come in cartridges, like the 110 and the 126: not to be confused with cassettes or canisters.