I have received a bad mark because of plagiarism?
It is important to note that I have used words from a dictionary to write an essay, but the professor told me that I have failed an assignment.
You have to make sure that you cite the correct source to avoid such issues in the future. It is understandable that you may think that there is no plagiarism in your paper.
However, a professor would not try to give you bad grades intentionally, and it is most likely your fault.
I do not think that you have told us everything this time because your story does not seem reasonable from the perspective of logic.
It is not possible that a teacher would give bad grades to students that did not reference the dictionary that they took words from because it sounds absurd.
It is possible that you made a mistake. The professor would not give you a bad mark if you just used the words. In my opinion, you have used some of the definitions that were in the dictionary, and the problem is that you cannot use ideas of others without proper citation.
The grade that you received is most likely appropriate in this case, and you should learn from this experience.
It is necessary to understand that plagiarism should be avoided at all cost because you may fail another assignment.
I am sorry that this happened to you. Can you tell me the topic of an essay that you had to write?
I would suggest you to ask the professor what you did wrong to have an understanding of what aspects you have to consider when working on an assignment.