What term describes unshared beliefs that lack evidence in reality?

The correct answer is the term "delusions." Delusions refer specifically to beliefs that are maintained despite being contradicted by reality or evidence. They are often persistent and strongly held, and the individual may be unaware of any contradiction or evidence against these beliefs. Delusions are typically seen in various mental health conditions, where a person's perception of reality is significantly distorted.

In contrast to delusions, myths, illusions, and fabrications have distinct characteristics. Myths are traditional stories or legends that often convey moral or cultural truths, but they do not necessarily lack a basis in reality; they may explain phenomena or cultural practices. Illusions involve a misperception of a real external stimulus, meaning there is some reality being perceived, but it is misinterpreted or distorted. Fabrications bring forth ideas or narratives constructed without factual basis but don’t necessarily imply a strong psychological attachment or conviction by the individual.

Therefore, "delusions" Is the most precise term for unshared beliefs that lack evidence in reality, particularly in a psychological context.