a large digital computer serving 100-400 users and occupying a special air-conditioned room
"The IT team had to evacuate the server room because their aging mainframe was overheating after running all night for hundreds of concurrent users."
(computer science) the part of a computer (a microprocessor chip) that does most of the data processing
"the CPU and the memory form the central part of a computer to which the peripherals are attached"
A large, powerful computer able to manage very many simultaneous tasks and communicate with very many connected terminals; used by large, complex organizations (such as banks and supermarkets) where continuously sustained operation is vital
"The bank's IT team spent the weekend upgrading their mainframe to ensure zero downtime during the holiday shopping rush."