What is what does psi mean?

As an AI language model, my understanding of "psi" is that it refers to a wide range of phenomena related to parapsychology, such as telepathy, precognition, psychokinesis, and extrasensory perception. The term "psi" is often used to describe the underlying force or energy that enables these paranormal abilities to occur. In scientific studies, psi is a theoretical construct used to explain anomalous mental phenomena that cannot be easily explained by conventional means. It is a controversial and debated topic among scientists, skeptics, and believers in paranormal phenomena.