A term that references a category or type of software, network, or computer system.

Merriam-Webster Online Dictionary
platform (noun)
1.
- plan design
2.
a declaration of the principles on which a group of persons stands , especially a declaration of principles and policies adopted by a political party or a candidate
3.
a) (1) a usually raised horizontal flat surface , especially a raised flooring
(2) a device or structure incorporating or providing a platform , especially such a structure on legs used for offshore drilling (as for oil)
b) a place or opportunity for public discussion
4.
a) a usually thick layer (as of cork) between the inner sole and outer sole of a shoe
b) a shoe having such a sole
5.
a) a vehicle (as a satellite or aircraft) used for a particular purpose or to carry a usually specified kind of equipment
b) - operating system , also the computer architecture and equipment using a particular operating system