Here are some examples:
* International: Between or among nations.
* Interpersonal: Between or among people.
* Interfaith: Between or among different religions.
* Interconnect: To connect mutually or between two or more things.
* Interact: To act upon or influence each other.
Note: While "inter-" is often used to indicate a relationship between two things, it can also be used to indicate a relationship among multiple things.