Pop/Soda/Coke

[GEORGE THOMPSON]

Natalie Maynor quotes a student as saying "Sodas are known as cokes
in the South.  Even Pepsi is called a coke in the South."

Does this mean that ginger ale and root beer and Dr. Pepper are
also called "coke"?  If so, how do they specify that they want or
are drinking a cola drink?  If Southerners were to be given a Dr.
Brown's Cel-Ray, what would they call it, other than a vile
concoction?

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