HOB

n. 1 a a flat heating surface for a pan on a cooker. b a flat metal shelf at the side of a fireplace, having its surface level with the top of the grate, used esp. for heating a pan etc. 2 a tool used for cutting gear-teeth etc. 3 a peg or pin used as a mark in quoits etc. 4 = HOBNAIL. [perh. var. of HUB, orig. = lump]