nail down
verb
nailed down; nailing down; nails down
1
: to make (something, such as a victory) certain to happen
They need to score another touchdown to nail down the victory.
2
: to find out or identify (something) exactly
Her doctors haven't yet been able to nail down a diagnosis.
They're trying to nail down the cause of our network problems.
3
: to make (something) definite or final
nail down a decision
Cite this Entry
“Nail down.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/nail%20down. Accessed 1 Sep. 2026.
Copy CitationLove words? Need even more definitions?
Merriam-Webster unabridged
