nail down

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

Idioms and Phrases

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]

Example Sentences

Clarke said he poured over recordings of the trial, listening to them first before he watched the videos, partly as a way to nail down the specificities of Alex’s accent and cadence.

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EU environment ministers will Tuesday make a last-ditch attempt to reassert the bloc's climate ambitions by nailing down key emissions targets in the run-up to the UN's climate summit in Brazil.

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The 22-year-old has already featured in two Six Nations campaigns but is yet to nail down a starting spot.

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County and plaintiff lawyers nailed down the $4-billion figure on Oct.

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They know nothing more about either man than they did in April – Pope missed his chance to nail down the spot and Bethell barely played.

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