The term is TONIC. In Boston, it's the generic term for Coke or any other soft drink. Actually, Coke is Coke and the rest of them are tonic.

Pop? Isn't that something pertaining to a weasel going somewhere? Soda? That's a concoction containing ice cream, syrup, milk and soda/seltzer water.

Soda water and seltzer water are interchangeable terms for a carbonated water used in mixed drinks and yes, ice cream sodas. Tonic water is a carbonated beverage flavored with quinine and also used in mixed drinks.

So there!
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