In the New York area it was either soda or just called by the brand name (Coke, Tab, Fresca, Manhattan Special, 7-UP, Sprite, Dr. Pepper, Crush (for Orange), Nehi (for Grape), Hires (for Root Beer), etc,,,) and of course here in the northeast Pepsi was as popular as Coke so both were used.  If you wanted a Canada Dry, that meant ginger ale.  I have heard tonic used throughout New England and pop in most other areas of the US.