main·​frame ˈmān-ˌfrām How to pronounce mainframe (audio)
: a large, powerful computer that can handle many tasks concurrently and is usually used commercially
… the million-dollar mainframe computers that took up entire floors of corporate premises …John Derbyshire
dated : a computer with its cabinet and internal circuits especially when considered separately from any peripherals connected to the computer

Example Sentences

Recent Examples on the Web Meanwhile, many of the IT systems that airlines depend upon were custom-built long ago, with some running on legacy mainframe computers, and weren’t designed to handle enormous surges of incoming information, aviation experts said. Brian Fung, CNN, 13 Jan. 2023 North Carolina Senator Sam Ervin declared that mainframe power posed a threat to the freedoms guaranteed by the Constitution. Margaret O'mara, Discover Magazine, 24 Sep. 2018 Our modern computing and business environments wouldn’t exist without the mainframe. Darío Gil, Fortune, 7 Nov. 2022 The Vietnam-era counterculture already had made mainframe computers into ominous symbols of a soul-crushing Establishment. Margaret O'mara, Discover Magazine, 24 Sep. 2018 Previous audits warned that the agency’s mainframe system, dating to the 1990s, was too rigid to handle complicated claims or rule changes, and relied too much on manual processes, leading to errors. From Usa Today Network And Wire Reports, USA TODAY, 29 July 2022 Take an airline ticketing system for example, there will be elements of cloud services involved for sure, but there will also be on-premises terrestrial mainframe systems underpinning the functions that surface at the user level. Adrian Bridgwater, Forbes, 11 Nov. 2022 In the 17th District, Democratic incumbent Markus Winkler was opposed by Republican Kent Hall, who is retired from the Jefferson County Clerk's Office, and William Bezoenik, an independent who is a mainframe engineer. Matthew Glowicki, The Courier-Journal, 8 Nov. 2022 Like the old-fashioned mainframe computers of a half-century ago, the QuEra machine can handle just one job at a time, so each user will have to wait his turn., 2 Nov. 2022 See More

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'mainframe.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

Word History

First Known Use

1957, in the meaning defined at sense 2

Time Traveler
The first known use of mainframe was in 1957

Dictionary Entries Near mainframe

Cite this Entry

“Mainframe.” Dictionary, Merriam-Webster, Accessed 28 Jan. 2023.

Kids Definition


main·​frame ˈmān-ˌfrām How to pronounce mainframe (audio)
: a large fast computer that can do many jobs at once

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