"Bio-real" is a word engineered by Capcom staff working behind the concept phase of Resident Evil titles. "Bio-real" defines concepts that are plausible in the fictional universe, that may not be in the real world - human cloning, for example, has been going on since the '70s in the series, while real-world development into mammalian cloning has progressed much slower and much later. The term is also used to differentiate between different concepts outside of the physical world - a Silent Hill-esque scenario involving parallel worlds is not "bio-real" as the paranormal does not exist in its universe.