"Demenz," the supposedly real name by which Professor Dementor is known, is merely a byproduct of "demented"; "dementor" implies one who forces dementia or a demented state, which surely suits Professor Dementor's goals, the "Professor" an additional qualifier, implying qualification for forcing dementia or a demented state. An alternative (and more tenuous) interpretation is that he represents the opposite qualities of a mentor, hence de - mentor (reversal or undoing of mentor).
Confidence: 80
