read-only

IPA/ˌriːd ˈəʊnli/
IPA/ˌriːd ˈəʊnli/

read-only — adjective

1. describes a computer file, document, or storage device that you can open and vie

1.adjectiveB1
Definition

describes a computer file, document, or storage device that you can open and view the contents of, but cannot edit, delete, or save changes to.

Example

Camila discovered the document was read-only and could not edit her notes.

Subject + discover + file was read-only

The system administrator set the configuration file to read-only to prevent accidental changes.

set to read-only + purpose clause

Common collocations
  • read-only file
  • read-only mode
  • read-only access
  • read-only memory
  • set to read-only
  • marked as read-only
  • change from read-only
Synonyms
  • protected

    broader term that can include password-based or permission-based restrictions beyond just preventing edits

  • locked

    informal term with similar meaning, but can also refer to files locked by other users or applications

  • non-writable

    purely technical term describing storage that does not allow writing; less common in everyday use

Antonyms
  • writable

    the direct technical opposite — a file or device that allows changes to be saved

  • editable

    general-purpose term describing content that can be modified using software

Grammar Patterns

be + read-only

marked as read-only

set to read-only

Usage Note

Frequently used both before a noun (a read-only file) and after verbs like 'be' or 'set to' (the file is read-only). In many operating systems, a lock icon next to the file name indicates read-only status.

Common Mistakes

I could not open the read-only file.
I opened the read-only file but could not edit it.
Read-only means you can view the contents; it does NOT mean the file is inaccessible.

Word family

Synonym discussion

Sense: adjective/1

All four terms describe restricted access to files, but they differ in scope and register. 'Read-only' is the most precise computing term — it specifically means the content can be viewed but not altered. 'Protected' is a broader term that may include password protection or permission-based restrictions. 'Locked' is more informal and can also mean a file is in use by another user. 'Non-writable' is a technical, less common term for storage that does not accept new data. 'Immutable' is the strongest term, used mainly in programming contexts to describe data that cannot change at all. For example: 'Camila opened the read-only document to check the figures.' vs 'The administrator locked the file while making backups.'

protected ↗locked ↗non-writableimmutable ↗

Etymology

Old EnglishMiddle EnglishModern English

The term was coined in the 1960s during the development of computer memory systems. It combines 'read' (from Old English 'rædan' — to interpret written characters) and 'only' (from Old English 'anlic' — single or solitary) to describe storage media whose content you can access but not alter. Originally used for punched cards and magnetic tape, it is now applied to files, folders, and memory chips alike.