'Flat' in the Bible

And at the sound of a long note on the horns, let all the people give a loud cry; and the wall of the town will come down flat, and all the people are to go straight forward.

So the people gave a loud cry, and the horns were sounded; and on hearing the horns the people gave a loud cry, and the wall came down flat, so that the people went up into the town, every man going straight before him, and they took the town.