No difference : in a midway position : neither one thing nor the other adverb/adjective However 'between' is often used these days in place of 'in between' which is a preposition. The lamp is in between/between the table and the wall.

"Betwixt" is a literary form not used in ordinary communication. A whimsical expression is "betwixt and between", which means "neither here nor there" or "not one thing or the other".

The word “betwixt,” by the way, is an old-fashioned version of “between,” though both words have been around in various forms since Anglo-Saxon times. I've not heard "betwixt" used in normal conversation. However, the expression “betwixt and between,” meaning neither one thing nor the other, is a relative newcomer. example--I'm betwixt and between canceling my trip entirely or just postponing it, or Austin is betwixt and between about accepting the offer.