soda
This term is predominantly used in North American English to describe a wide range of sparkling beverages. In different regions of the United States, it competes with the term pop, creating a distinct geographic linguistic divide. It carries a casual, refreshing connotation associated with fast food and social gatherings.
Technically, the word refers to the sodium salts or the carbonation process, but in a social context, it implies a sugary, bubbly treat. It is rarely used in formal dining settings, where terms like sparkling water or soft drink might be preferred to avoid a childish or overly casual tone.
Uncountable when referring to the liquid substance in general (There is soda on the floor). Countable when referring to an individual serving or a can (I bought two sodas).