Definition of the word unreal

"Unreal" traces back to the Old English word "unrēal," meaning "not real." It's a combination of the negative prefix "un-" and "real," which itself evolved from the Old French "real" and ultimately from the Latin "rēālis" meaning "royal," "pertaining to a king," or "belonging to the realm." Thus, the original sense of "real" referred to something belonging to the king, or to the kingdom, implying authority and authenticity. The addition of "un-" created the opposite, signifying something not authentic or genuine, and eventually came to describe something not existing or not conforming to reality.