What term describes an instructor that claims knowledge or skills that they don't possess?

The term that describes an instructor who claims knowledge or skills that they do not possess is "charlatan." This word specifically refers to someone who falsely pretends to have knowledge or qualifications, often to deceive others for personal gain. In an educational context, a charlatan might present themselves as an expert in a subject, misleading students and undermining the integrity of the learning environment.

This distinction is important as it highlights the ethical responsibilities of instructors to be truthful about their qualifications and the potential harm that can arise when someone misrepresents their capabilities. It also emphasizes the need for students to critically evaluate instructors' credentials and the authenticity of their expertise.

While the other terms may relate to deceit in various contexts, they do not capture the specific connotation of fraudulent professional representation as effectively as "charlatan" does, making it the most appropriate term for this scenario.