1 : a state of connectedness between people (especially an emotional connection)
2 : a state involving mutual dealings between people or parties or countries
3 : a usually secretive or illicit sexual relationship
4 : an abstraction belonging to or characteristic of two entities or parts together
5 : an essay (especially one written as an assignment)
6 : a relation between things or events (as in the case of one causing the other or sharing features with it)