vocabulary - Differences between "vulgar" and "coarse", "crass", "crude", "rough", "rude", "unrefined" as applied to language

This question specifically covers how these terms are used to describe language, it is a followup to What's the difference between "informal", "colloquial", "slang", and "vulgar"?

In the former question it arose that vulgar has at least two senses, and perhaps three:

• "of the people" as in Vulgar Latin (not considered to be a productive sense anymore)


• an antonym to "refined" as used to label words in various dictionaries


• a synonym for "obscene" or "offensive" - I take this sense to be newer and perhaps regional to America - but it does seem to be replacing sense 2

So my question is how do these other words overlap in meaning with the 2nd and 3rd senses above: "coarse", "crass", "crude", "rough", "rude", "unrefined"?