noun Chiefly South Midland U.S.
Examples from the Web for mantelboard
Then he came back to the fireplace, and leaned against the mantelboard.The Giant's Robe|F. Anstey
In fact, it is quite a mantelboard ornament, as most of these things are.Sharps and Flats|John Nevil Maskelyne
Tunisian or point lace forms a very good edging to a mantelboard, and when a foot deep, or nearly so, it is extremely handsome.Household Organization|Florence Caddy