ATH'ANOR, noun [Heb. thanor, an oven or furnace.] A digesting furnace, formerly used in chimical operations, so constructed as to maintain a uniform and durable heat. It is a furnace, with a lateral tower close on all sides, which is to be filled with fuel. As the fuel below is consumed, that in the tower falls down to supply its place.
Source: Webster's 1828 American Dictionary ↗ · public-domain · returned verbatim, no AI