A term used to describe something that is so abstract, intangible, or hypothetical that it exists only in theory or imagination and cannot be proven to exist in reality. It's a blend of "unexist" (not existing) and "ability" (the quality or state of being capable).
Person 1: "Do you think there's life on other planets?"
Person 2: "It's an intriguing question, but until we have concreteevidence, it remains in the realm of unexistability, existing only in our imaginations and scientific theories."
Pajama casual is a term used when working from home and preparing for a video conference. All business above the waist and your pajama pants down below.