cattle-guard
A wide and deep trench cut across a railway (under the rails), on each side of a level crossing, to prevent cattle from straying along the line; a ‘cow-pit’. (In U.S.)
| 1843 in Edwards Chancery Cases III. 489 The first cattle guards he saw were in one thousand eight hundred and thirty six. 1881 Chicago Times 14 May, The night was..dark, and in groping along the track the negro fell into a cattle-guard. |