set in stone
permanent; not subject to change
In Spanish
escrito en piedra, inmutable
Examples
- Nothing about the design is set in stone — we'll iterate based on feedback.
- The schedule is not set in stone, so we can still make changes.
- Her decision isn't set in stone; she might change her mind later.
When it's used
The idiom is used in English to indicate that something is permanent or unchangeable. It is common in both informal and formal contexts, in speech and writing. It is frequently used in discussions about plans or decisions.
The common mistake
A common mistake is using 'written in stone' directly in English, calqued from Spanish 'escrito en piedra'. While the idea is similar, 'written in stone' is not a recognized idiomatic expression in English. The correct form is 'set in stone'.