pin down

present singular third person pins down · participle present pinning down · participle past pinned down · past pinned down

1. transitiveTo attach or secure with pins.

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

   1 more example

   There are approximately 1,000 places on British Railways where wagon brakes must be pinned down before trains proceed over severe falling gradients; the trains have to be brought to a stand for the brakes to be pinned down, and subsequently have again to be stopped for the brakes to be released.

   1955 March, “Modernisation and Re-Equipment of British Railways”, in Railway Magazine, pages 154, 171

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

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

3. transitivegovernmentTo hold the opponent back-first so both his or her shoulders touch the mat or ground.

   Synonyms: pin

4. idiomatictransitiveTo corner somebody in order to get a firm answer.

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