A Hand Wave (also memetically called "Scotch Tape") is any flimsy explanation - particularly involving the backstory, a retcon, or a use of phlebotinum - which is noteworthy for its lack of detail or coherence. It may be used to (try to) hold together an Idiot Plot or an otherwise outrageous story. Often consists of throwaway lines like "Its The Only Way." The name comes from academia, initially [...] [tvtropes.org]