coke (n.1) Look up coke at Dictionary.com
"residue of fuel," 1690s, northern English dialect, perhaps a variant of Middle English colke "core, charcoal" (c. 1400), itself possibly related to -colc, an Old English word for "pit," which perhaps would give it a sense of "what is left in the pit after a fire."
Coke Look up Coke at Dictionary.com
soft drink, 1909, shortening of brand name Coca-Cola.
coke (n.2) Look up coke at Dictionary.com
shortened form of cocaine, 1908, American English.