The Collaborative International Dictionary
Grate surface
Grate \Grate\, n. [LL. grata, fr. L. crates hurdle; or It. grata, of the same origin. Sae Crate, Hurdle.]
A structure or frame containing parallel or crosed bars, with interstices; a kind of latticework, such as is used ia the windows of prisons and cloisters. ``A secret grate of iron bars.''
--Shak.-
A frame or bed, or kind of basket, of iron bars, for holding fuel while burning.
Grate surface (Steam, Boiler) the area of the surface of the grate upon which the fuel lies in the furnace.