Webster’s Revised Unabridged Dictionary · 1913
Coke
Coke (kōk), n. [Perh. akin to cake, n.] Mineral coal charred, or depriver of its bitumen, sulphur, or other volatile matter by roasting in a kiln or oven, or by distillation, as in gas works. It is lagerly used where a smokeless fire is required. [Written also coak.]
Gas coke, the coke formed in gas retorts, as distinguished from that made in ovens.
Coke, v. t. To convert into coke.