A wrongcept is similar to a misconception but includes all concepts or beliefs that are incorrect or fundamentally flawed, not just those flawed because of faulty understanding. For instance many people belief things that are based on urban myths, and do so because they have incomplete or inaccurate information passed on others who failed to check their references.
Many people believe that a vomitorium was a room used by Romans for purging food during meals. It is actually the entranceway through which crowds entered and exited a stadium. The concept of Romans having a room to vomit in during meals is just plain wrong and not based on any sound information, it is a wrongcept.
Recent design concepts for mobile devices include translucent displays, completely ignoring the fact that between reflections and back-lighting they will render most information they display invisible. This concept makes no sense at all to anyone who has used a mobile device, it is patently flawed and a wrongcept.