Boundaries boundaries boundaries boundaries boundaries. Basically, this needs to be an exercise in teaching him that if he behaves unpleasantly towards you, he won't get to spend time with you. So, if he starts swearing at you and calling you names, say "You are swearing at me and calling me names. Please stop, or I will end this conversation." He probably won't stop, at which point you leave the room. Rinse and repeat as necessary until it sticks. It will be really,
really awkward (as it should be, because
he is behaving in a way that makes it awkward). Other family members will probably be shocked and tell you you're being disrespectful and/or that he's just like that, and you should just go along with it for a quiet life. Tell them that's interesting and you'll think about it. Then carry on stating and enforcing your boundaries. Eventually, he'll get the point.
In order to make this work, you need to be ready, able and prepared to leave the room, or the building, or if necessary the holiday, so you may want to have some contingency plans regarding e.g. transport. You're in quite a good position here, because you don't live at home and therefore I'm assuming you aren't dependant on your parents anymore? So, just leaving is an option.
Captain Awkward is a great resource for this sort of boundary-setting and enforcing. Take a look through the archives for situations similar to yours, and you'll probably find lots of ideas. Good luck!