pin down

pin down (see inflection at pin) (transitive)

1. To attach or secure with pins.

   Pin down the tablecloth, so it doesn't blow away in the breeze.

2. (idiomatic) To identify something (e.g. a decision or plan) clearly or specifically.

   Something is wrong, but I can't pin it down.

3. (wrestling) To hold the opponent back-first so both his or her shoulders touch the mat.
4. (idiomatic) To corner somebody in order to get a firm answer.

   Let's try to pin him down on a price.

• unpindownable

• nail down