To enter into a situation or begin a process or journey that is particularly strange, problematic, difficult, complex, or chaotic, especially one that becomes increasingly so as it develops or unfolds. (An allusion to Alice's Adventures in Wonderland by Lewis Carroll.) Owning your own business is a huge responsibility that not everyone is prepared for. Are you sure you're ready to go down the rabbit hole? I've stayed away from drugs and alcohol since coming to college. I have an addictive personality, so I decided to just avoid going down that rabbit hole altogether. Overhauling the current tax legislation is a rabbit hole I don't think this administration should go down at this point.