1 B2 idiomatic neutral
To reach a definite agreement or decision, especially after negotiation.
"After weeks of talks, the two companies finally nailed down the terms of the contract."
separable
nail down
B2 neutral separable transitive
To firmly establish, confirm, or settle something such as a deal, plan, or fact.
In plain English
To make sure something is definite and cannot change, like the details of a plan.
What does "nail down" mean?
4 meanings, ordered from most common to least. Color-coded by CEFR level.
2 B2 idiomatic neutral
To identify or define something precisely, such as a problem, cause, or meaning.
"Scientists are working to nail down exactly what triggers the allergic reaction."
separable
3 A2 neutral
To physically fix something in place using nails.
"He nailed down the loose floorboards so no one would trip."
separable
4 C1 idiomatic informal
To force someone to state their position or commit to something clearly.
"The interviewer tried to nail the politician down on his tax policy."
separable
Literal vs figurative
Words literally mean
To hammer nails downward to fix something firmly in place, like a lid on a crate.
Actually means
To make sure something is definite and cannot change, like the details of a plan.
Usage tip
Very common in business and journalistic contexts. Often used with nouns like 'deal', 'date', 'details', 'meaning'. Can also mean to physically fix something with nails, though the figurative sense is far more frequent.
Words that pair with "nail down"
Natural word combinations native speakers use most often.
deal details date agreement meaning location
How to conjugate "nail down"
The five tense forms you'll use most often.
Base
nail down
I/you/we/they
3rd person
nails down
he/she/it
Past simple
nailed down
yesterday
Past participle
nailed down
have + pp
-ing form
nailing down
continuous
Hear "nail down" in the wild
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Other ways to say "nail down"
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Keep exploring
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