These questions always puzzle me a bit; they never come up because someone's conflicted about how they should communicate - they're always attached in some fashion to the notion that there should be limits on how other people should be interpreting what you've written:
I'm simply talking about vocabulary, not intent or context.
Yes, because words are unambiguous and always interpreted the same way by every reader, right? Riiiight.
Let's go back to the original intent of chat:
I think a web-based real time chat system like Campfire could offer that informal public gathering third place — a space for people who love the topic to meet, discuss, and collaborate in a different way. It would foster community, and be complementary to both strict Q&A, and meta-discussion.
So, a less-formal meeting place for folks to chew the fat a bit while discussing the topics that brought them together in the first place, getting to know one another, etc. This is captured in chat's FAQ:
This site is an extension of The Stack Exchange Network, so discussion should more or less revolve around the same topics you'd find at The Stack Exchange Network — but in an interactive, less strictly Q&A focused way. Do have fun, but please keep it professional and always be respectful of your fellow community members.
Is cussin' "professional"? Well, I've had a few different professions, and a certain amount of vulgarity was definitely commonplace in some of them. In an informal setting like chat, I think it's acceptable to use common language, to be a bit less rigid in what you expect, and punctuating your speech with the occasional bit of blue shouldn't be looked at too harshly. That said...
You do not get to tell anyone else what offends them, not here, not on the main sites, and not in chat. Ever.
This goes beyond vulgar language. Most of chat is public, and if the folks reading what you're writing are offended, then you can either stop writing it or go somewhere else.
In particular, when you're hanging out in the primary chat room for a given site, you should assume that the folks using that site will stop in and read it now and then. If you find yourself writing something that wouldn't be acceptable on http://genealogy.stackexchange.com/, maybe you shouldn't be dropping it into Roots either. Get your own room - they're free.
Oh yeah - read the FAQ. If you do say something that gets under folks' skin and find yourself blocked for a half-hour or so, you can't say we didn't warn you. If you really insist on being an ass about it, we can and will suspend you from the main sites as well based on your behavior in chat - so consider that half-hour a gentle warning, a chance to get a cup of coffee and re-think what you're doing.