I often wonder how formal a words or expression is (e.g. Is “by way of conclusion" more formal than "In conclusion"?). Is there some comprehensive reference that would list the level of formality of words and expressions as accurately as possible?
Ideally I would like to have some crowd-sourced judgment, like Urban Dictionary does for validating a word:
Beyond the level of formality I would also be interested in knowing whether the word or expression sounds flatulent, pejorative, etc: anything that indicate what underlying "feeling" a word or expression conveys when we use it.