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

They have a fair amount of experience in various batting positions, although neither has been consistent to nail down a place.

From BBC ● Jul. 12, 2026

If one had to nail down the central theme of “The Audacity,” aside from pure human foible, it would be the perils posed to privacy by the profitability of data.

From The Wall Street Journal ● Apr. 9, 2026

Their numbers are hard to nail down, but in the first half of 2025, nearly 4 in 10 new vehicle registrations were hybrid and EV variants.

From Los Angeles Times ● Mar. 26, 2026

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

From "Patina" by Jason Reynolds