The hearth of a metal-forging shop; the forge of a smithy. / An enclosed hearth with hatch for refueling that is attached to or built into a boiler that supplies steam for mechanical power.

Alternative form of forward compatible

The opening price for an item at an auction. / (horse racing) The final odds on a horse when the race starts; also used to designate a system of fixed-odds betting using such prices. Abbreviation: SP.

(rare) Able to be accompanied.