It means "Go away" or "Leave".
Example:
* "Vayanse de aquí" - "Go away from here"
* "Vayanse a casa" - "Go home"
It is important to note that "vayanse" is a formal and polite way of telling someone to leave. In a more informal setting, you could use "vete" or "vete de aquí" to tell one person to leave.