Accordingly, what does the curse mark mean?
The Curse Mark is the juinjutsu that were one of the most frequently-used technique of Orochimaru, which he usually gave to his most powerful and unique followers. To apply a cursed mark, Orochimaru needed to bite his intended target. As he had sharp fangs and an extendible neck, this was a relatively simple task.
Also, can a curse mark be removed? This will be a very closely guarded secret as with this knowledge the branch family can simply break off from the main branch's dominance. I don't think this was every discussed in Naruto. So yes, it's highly possible to have the curse mark removed without killing the person, provided they know the undoing technique.
Similarly, what if Sasuke still has Curse Mark?
How much stronger would Sasuke be if he still had the curse mark? Not at all. Kakashi said that if he continued using it, his growth and power would be severely stunted.
What episode does Sasuke get his curse mark removed?
During Sasuke's battle with Itachi Uchiha, he lost the cursed seal, along with Orochimaru (having earlier been absorbed into Sasuke's body), as they were removed with the Sword of Totsuka.