# mainframe

/ˈmeɪnˌfɹeɪm/ (US) · /mˈeɪnfɹeɪm/ (UK) · CEFR C1 · Noun

Source: https://englishreference.com/word/mainframe
Updated: 2026-07-22

## Definition

a very large and powerful computer used by big companies or governments to handle huge amounts of data.

For teachers: a high-performance computer system designed for high-volume data processing and critical applications requiring extreme reliability.

## Examples

- The bank uses a mainframe to process millions of transactions every day.
- While many companies have moved to the cloud, some still rely on a central mainframe for their most sensitive financial records.
- The transition from legacy mainframe architecture to distributed cloud systems remains a significant technical challenge for many established government agencies.

## Usage notes

- Often used as a modifier before other nouns, such as 'mainframe computer' or 'mainframe system'.

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