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

"I've had a few teams, I've had some very good years and some tougher years, but when this opportunity came up, I jumped at it. I wanted to nail down that shirt."

From BBC ● Jun. 4, 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

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

Then he threw the nail down and rested one ragged sneaker on the fish.

From "Mississippi Trial, 1955" by Chris Crowe