They cursed us. Murderer they called us. They cursed us, and drove us away. And we wept, Precious, we wept to be so alone. And we only wish to catch fish so juicy sweet. And we forgot the taste of bread... the sound of trees... the softness of the wind. We even forgot our own name. My Precious.
~ Gollum in Lord of the Rings: Return of the King.

In my day, we had fantastical feasts when I lived in the palace. And now, look at me--wasted away to practically nothing. Banished and exiled and practically starving! While he and his flimsy fish-folk celebrate. Well, I'll give 'em something to celebrate soon enough.
~ Ursula seeking to avenge her banishment as well as her revenge against King Triton's court and rule Atlantica for herself.

An Outcast, often referred to as an "Outsider", is basically another name for an exiled character or being. Unlike the Imprisoned villain, an Outcast is banished without actually being imprisoned; sometimes, being exiled is seen as sufficient punishment in itself or they are away from civilization and society by choice. Many Outcast characters seek to return to their previous power or position; others are driven mad or embittered by it. Very few embrace the state of exile. Sometimes, outcasts can be people who either got rejected by civilization and society, or they rejected civilization and society.

Alternatively, on smaller scales, an Outcast can be someone who is not socially accepted, being hated and/or feared by those around him/herself, forcing them into a life of relative isolation and/or wandering. By definition, these are the opposite of Charismatic villains and are usually Tragic as well.