The plural form of "Smoothy" should stay "Smoothies", however the singular form should end in a "y" not an "ie" such as the word "puppy" and the plural form "puppies", it is also visually appealing and good for advertisement as its connotation relates to positive and refreshing feelings. However some may say that "Smoothie" should stay the same, I believe they have no evidence or passion on the subject, they are not doing justice to the fun word it could be, when we think of smoothies, we think of summer and fun drink. Looking at the word "smoothie" it should follow that suit, however I find myself disliking the word and finding it unnatural. As the suffix of "ie" does not tickle my fancy, the "y" in "smoothy" however is much more pleasurable.