Scrimmage down

Context might help.

In American football, it is a play where the officials put the football down on the field at a certain spot dictated by the play before, and the football is snapped between the legs of the center and a play begins. The offensive team has downs from the original line of scrimmage, (the place where the ball rests on the first play), to make 10 yards or the ball goes over to the other team. Here is an example of 10 scrimmage downs:

And here are some more:



Here is a video that explains American football for beginners. The "downs" the narrator refers to at the 29 second mark are the common name for "scrimmage downs".