Answer: mainframe

AnswerCrossword Clue
MAINFRAMESource of a download
MAINFRAMEComputer master's at home with brother and me (9)
MAINFRAMEDesktop's big brother
MAINFRAMEType of computer
mainframea large computer serving others
mainframeA large high-speed computer, esp. one supporting numerous workstations or peripherals
mainframeThe central processing unit and primary memory of a computer