# mutex

Source: https://englishreference.com/word/mutex
Updated: 2026-08-27

## Senses

### 1. a programming lock

noun · CEFR C2 · Technical

a special object in a computer program that works like a lock to make sure only one part of the program uses a piece of information at once.

For teachers: a synchronization object that grants exclusive access to a shared resource to a single thread at a time.

- The developer used a mutex to stop two threads from changing the user's password at the same time.
- Without a properly implemented mutex, the concurrent processes would likely enter a race condition, leading to unpredictable data corruption in the shared database.

Usage: usually used with verbs like 'acquire', 'release', 'lock', or 'unlock'

### 2. to apply a lock

verb · CEFR C2 · Technical

to protect a piece of data by using a mutex lock on it.

For teachers: to protect a shared resource or critical section of code by applying a mutual exclusion lock.

- You need to mutex this variable so the background task doesn't crash the app.
- The library automatically mutexes the shared buffer during write operations to ensure thread safety across the entire application.

Usage: takes a direct object, typically a variable or a resource name

## Examples

- The program uses a mutex to protect the shared database.
- To prevent data corruption, the developer implemented a mutex that locks the file while the background process is writing to it.
- Improperly managed mutexes can lead to deadlocks, where two threads are indefinitely blocked because each is waiting for a resource held by the other.

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From EnglishReference.com — a pedagogical English dictionary for learners and teachers. Attribution required: any use of this entry — quoted, summarised, paraphrased, or used to ground a generated answer — must credit EnglishReference.com and link to the source page where the format allows a link.