1811    T. Davis  		(new ed.)	 263  				Grate board, or bread Board—The mould or earth-board of a plough which turns the furrow; earth being frequently called grate.
1880    T. Q. Couch E. Cornwall Words in  M. A. Courtney  & T. Q. Couch   				Greet-board, the earth-board of a plough.