I am not sure if there are any real definitions of what is exactly a dialect.Originally Posted by kalinka_vinnie
But, as far as Ukrainian and Russian go, different vocabulary, different alphabet, different grammar and different phonetics suggest that they are actually different languages, as common wisdom accepts it.
Polish is understandable to me, probably to a similar degree to how Ukrainian is understandable to a Russian person without any prior exposure. This does not mean that Polish is a dialect of Russian (or Ukrainian).
I actually have doubts about Cantonese too -- it is quite common to see it being referred to as "Cantonese language". Probably political considerations are the main reason it has not yet attained a formal language status in China (but as we know these are always subject to change).