Quote Originally Posted by Loony BoB
Oh. Haha, well, soda defaults to 'soft drink' in dictionary.com, so that pretty much says it all, then.
That is because soda has one alternate definition. Pop on the other hand is used for way to many things.

Pop as in papa(father)
Pop music
Pop...ulation
Pop - soft drink
POP - Point Of Purchase
POP - Proof Of Purchase

All of these are listed in the definition but since pop is a very versitile word it couldn't just put one of its slang terms on the top like they do for soda. Not to mention that pop can be used as a noun, adverb, verb and maybe even an adjective.