its like a dictionary, except it gives synonyms for words. A thesaurus is similar to a dictionary, but instead of definitions, it will give you synonyms (similar words) and antonyms (opposites) of the words listed. it provides words that mean the same thing!
The positive connotation of "slouched" could be seen as relaxed or casual. This posture may suggest a sense of ease or comfort, especially in informal settings. It can also convey a laid-back attitude or a nonchalant demeanor.
A person who speaks their mind with vulgarity would be considered opinionated and coarse and one word that describe this combination put into action might be "flyting" as described below from the search thersaurus :flyting, a slanging match in verse, usually between two poets who insult each other alternately in profanely abusive verses.