Webster’s Revised Unabridged Dictionary · 1913
Athanor
Ath′a·nor (ăth′ȧ·nôr), n. [F., fr. Ar. at-tannūr, fr. Heb. tannūr an oven or furnace.] A digesting furnace, formerly used by alchemists. It was so constructed as to maintain uniform and durable heat. Chambers.