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Synonyms

mainframe

American  
[meyn-freym] / ˈmeɪnˌfreɪm /

noun

Computers.

  1. a large computer, often the hub of a system serving many users.

mainframe British  
/ ˈmeɪnˌfreɪm /

noun

    1. a high-speed general-purpose computer, usually with a large storage capacity

    2. ( as modifier )

      mainframe systems

  2. the central processing unit of a computer

"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012
mainframe Scientific  
/ mān′frām′ /

  1. A large, often powerful computer, usually dedicated to lengthy, complex calculations or set up for use by many people simultaneously.

  2. Compare personal computer

mainframe Cultural  

  1. A large, powerful computer system. A mainframe computer typically carries out complex calculations and is shared by many users. (Compare personal computer.)

Etymology

Origin of mainframe

First recorded in 1960–65; main 1 + frame

Compare meaning

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Vocabulary lists containing mainframe

Computer Science and Technology - Middle School

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Computer Science and Technology - High School

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Example Sentences

Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.

“It was a shot to the heart and the chest and the mainframe with Luka,” James told reporters.

From Los Angeles Times • Apr. 9, 2026

There is a perception that IBM’s mainframe business could be threatened by AI.

From Barron's • Mar. 27, 2026

“The idea of shifting off of mainframe is not a new concept,” Daryanani concluded.

From Barron's • Feb. 24, 2026

“Software and mainframe performance supported strong results for what many consider a defensive name,” said JPMorgan analyst Brian Essex, who rates the stock a neutral.

From MarketWatch • Jan. 29, 2026

A few seconds after my eargear was attached and activated, I began to hear the placid monotone of the HR mainframe, droning instructions and other information.

From "Ready Player One: A Novel" by Ernest Cline

Definitions and idiom definitions from Dictionary.com Unabridged, based on the Random House Unabridged Dictionary, © Random House, Inc. 2023

Idioms from The American Heritage® Idioms Dictionary copyright © 2002, 2001, 1995 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company.