nail down

British  

verb

1. to fasten down with or as if with nails

2. informal to extort a definite promise or consent from

   I nailed him down on the deadline

3. informal to settle in a definite way

   they nailed down the agreement

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nail down Idioms  

1. Establish conclusively, as in The reporter nailed down the story by checking all the facts. This metaphoric expression alludes to fixing or fastening something down with nails. [c. 1600]

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Example Sentences

See Examples For:

nail down

Moreover, given the company’s products and offerings are at different stages of maturity, growth and decline, it’s been challenging for investors to nail down the company’s prospects given its complex structure, Moerdler wrote.

From MarketWatch ● Sep. 2, 2026

She gave them until early May to nail down a plan, otherwise they’d stick with the existing part.

From The Wall Street Journal ● May 5, 2026

When Rupert’s children watched its too-close-for-comfort version of the chaos following Logan Roy’s sudden death, they leapt to nail down their family’s succession plan before it was too late.

From Salon ● Mar. 14, 2026

The death toll in Iran has been difficult to nail down, but Iran’s ambassador to the U.N. on Friday put the number at more than 1,300.

From Los Angeles Times ● Mar. 8, 2026

On Friday all we did was nail down who we were going to focus on.

From "Patina" by Jason Reynolds