# nail down

idiom

Source: https://englishreference.com/idiom/nail-down
Updated: 2026-08-10

## Meaning

to make something (e.g. a decision or plan) firm or certain

## Examples

- We need to nail down the date for the party.
- After weeks of discussion, the team finally nailed down the details of the new project.
- The diplomats worked through the night to nail down an agreement before the deadline, knowing that any ambiguity could unravel months of careful negotiation.

---

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.