1. the time by which something must be finished, submitted, etc. 2. (formerly) a boundary around a military prison beyond which a prisoner could not venture without risk of being shot by the guards.
While it's important to talk with your doctor about the cause of your slurred speech, slurred speech caused by anxiety is not dangerous. It's not a sign that you have something else coming, or that your brain will somehow be inefficient for handling life tasks in the future.
Plagiarism may occur when a person fails to place quotation marks around someone else's exact words, directly rephrasing or paraphrasing someone else's words while still following the general form of the original, and/or failing to issue the proper citation to one's source material.