Definitions
1.nounThe package consisting of the bullet, primer, and casing containing gunpowder; a round of ammunition.
2.noun(by extension) A prefabricated subassembly that can be easily installed in or removed from a larger mechanism or replaced with another interchangeable subassembly.
3.nounA vessel which contains the ink or toner for a computer printer and can be easily replaced with another.
4.nounMagnetic tape storage, used for storing (backup) copies of data.
5.nounA removable enclosure containing read-only memory devices, used for rapid loading of software onto a home computer or video game console.
6.nounA small paper package, e.g. in an old book about making printer's type: After all the type has been cast: "The Boy will paper up each sort in a cartridge by itself".