coke

Etymology 1

Perhaps from Middle English colk (“core”).

noun

1. (uncountable) Solid residue from roasting coal in a coke oven; used principally as a fuel and in the production of steel and formerly as a domestic fuel.
   The plant should produce approximately 550,000 tons of screened blast furnace coke per year.
   At Ho-pi (Hopi) in northern Honan two modern shafts were under construction in 1957-8; but the coal from Ho-pi is expected to be of rather poor quality and so will be mixed with rich coal from P'ing-ting-shan (Pingtingshan) in central Honan for coke making. 1963, “The Coal Industry in Mainland China Since 1949”, in The Geographical Journal, volume 129, number 3, →ISSN, →JSTOR, →OCLC, page 333

verb

1. (transitive) To produce coke from coal.
2. (intransitive) To turn into coke.
3. (especially automotive, astronautics) To add deleterious carbon deposits as a byproduct of combustion.
   In kerolox engines, some of the fuel flow cokes in the engine's cooling passages over time, requiring thorough cleaning prior to reuse.

Etymology 2

Originated circa 1908 in American English as a clipping of cocaine.

noun

1. (informal, slang, uncountable) Cocaine.

Etymology 3

1909, from the name of the American company Coca-Cola and the beverage it produced; the drink was named for two of its original ingredients, coca leaves and cola nut.

noun

1. (uncountable, informal) Alternative letter-case form of Coke (cola-based soft drink, especially Coca-Cola).
2. (countable, informal) Alternative letter-case form of Coke (a serving of cola-based soft drink, especially Coca-Cola).
3. (US, chiefly Southern US, informal) Alternative letter-case form of Coke (any soft drink, regardless of type).