"Plagiarism is the act of a person presenting another person's work as if it were his or her original work." NCC Plagiarism policy, Student Handbook
If you ask ChatGPT, it will generate an explanation of why using it is not plagiarism in the traditional sense but will also stress the need to attribute information sources, including itself.
In the case of using answers generated by chat AI technology, it can be argued that it is not plagiarism because the answers are not the work of a single individual, but rather the result of a complex algorithm that draws from a vast amount of data and sources.
Can’t I just tell students they’re not allowed to use ChatGPT and then use tools to identify when they have used it?
First, anytime we rely too heavily on policing or heavy-handed policies we run the risk of undermining trust in our classrooms. And research shows that building trust in the educational setting is an important component of student learning and success. Secondly, the reality is that any attempt to police this kind of activity is likely to turn into an arms race. Artificial intelligence tools aren’t going to go away, and they are only going to get better. While there are tools out there that can review text and make a prediction about whether or not student work has been artificially generated, they are not foolproof, and as they become better, we can probably be certain AI will evolve to outwit them.
from The Intersection of AI and Pedagogy, Plymouth State University Open Learning and Teaching Collaborative (January 2023)