pin down

verb

1. to force (someone) to make a decision or carry out a promise
2. to define clearly

   he had a vague suspicion that he couldn't quite pin down

3. to confine to a place

   the fallen tree pinned him down

Example Sentences

But pinning down the exact triggers for migration is challenging.

From BBC

Wade through his Supreme Court appointments, he’s been harder to pin down on his plans for abortion in a second term.

From Los Angeles Times

With the polls showing a razor-thin difference between Harris and Trump among those who have indeed made up their minds, it’s hard to pin down exactly how many people may still be undecided.

From Salon

“Rufus-Retro-Wainwright-Spective” will offer a crash course in a critically vaunted musician who has a passionate cult following — including many Hollywood stars — but who has always been a little hard to pin down.

From Los Angeles Times

It is not a thing you can pin down, you can get better at it, but will never be 100% perfect.

From Los Angeles Times