Names for soft drinks in the United States vary regionally. "Soda" and "pop" are the most common terms for soft drinks nationally, although other terms are used, especially "coke" in the South. Since individual names tend to dominate regionally, the use of a particular term can be an act of geographic identity. The choice of terminology is most closely associated with geographic origin, rather than other factors such as race, age, or income. The differences in naming have been the subject of scholarly studies. Cambridge linguist Bert Vaux, in particular, has studied the "pop vs. soda debate" in conjunction with other regional vocabularies of American English.
History
According to writer Andrew Schloss, "soda" derives from sodium, a common mineral in natural springs, and was first used to describe carbonation in 1802. The earliest known usage of "pop" is from 1812; in a letter to his wife, poet Robert Southey says the drink is "called pop because pop goes the cork when it is drawn, & pop you would go off too if you drank too much of it." The two words were later combined into "soda pop" in 1863. Schloss gives the following years as the first attestations of the various terms for these beverages:
"Soda" is most common on the East and West Coasts, as well as Hawaii, St. Louis, Missouri, and Milwaukee, Wisconsin. It is also known as a fizzy. The "soda/pop" dialect line runs through Western New York State, approximately through the Rochester, New York area. Those west of the line say "pop" while those east of the line use "soda."
Other names
"Tonic" has been used in eastern Massachusetts and parts of Maine and New Hampshire since at least 1888. Its usage has been gradually declining in favor of "soda". In some areas, "tonic" is still understood to mean "soft drink", but many regard it as an antiquated term.
"Soda pop" is used by some speakers, especially in the Mountain West. "Soda" or "drinks" is common in Idaho and Utah.
"Drink", "cold drink", "carbo", and "soda" are locally common in southern Virginia and the Carolinas, spreading from there as far as Louisiana.
"Soda water" is used in more rural parts of the US.
At many restaurants in the U.S., the products of only a single major beverage producer, such as The Coca-Cola Company or PepsiCo, are available. While most patrons requesting a "coke" may be truly indifferent as to which cola brand they receive, the careful server will confirm intent with a question like "Is Pepsi OK?" Similarly, 7 Up or Sprite or Sierra Mist may indicate any clear, carbonated, citrus-flavored drink at hand. The generic uses of these brand names does not affect the local usage of the words "pop" or "soda" to mean any carbonated beverage.
