pin down

See also: pindown

English

pin down (third-person singular simple present pins down, present participle pinning down, simple past and past participle pinned down) (transitive)

To attach or secure with pins.
Coordinate terms: pin up, tack up

Pin down the tablecloth, so it doesn't blow away in the breeze.
- 1955 March, “Modernisation and Re-Equipment of British Railways”, in Railway Magazine, pages 154, 171:
  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.
(idiomatic) To identify something (e.g. a decision or plan) clearly or specifically.
Something is wrong, but I can't pin it down.
(wrestling) To hold the opponent back-first so both his or her shoulders touch the mat or ground.
Synonym: pin
(idiomatic) To corner somebody in order to get a firm answer.
Let's try to pin him down on a price.

to attach with pins